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wesmigletz Engine swap on the C1
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I pulled the 62's original 327/300 HP engine a few weeks back, in anticipation of some part swapping and dyno testing. The testing is on hold for now, but since I had the engine out, I'm going to go ahead and swap my old truck's 383 back in.

The engine is an 010 350 block, with 4 bolt mains, and .030" over bore. Fresh rings and bearings since I pulled it back out of the 62. An externally balanced 3.75" stroke, 5.7" rods, 12 CC dished pistons.

It has an Engle HR cam with .492/.501" 223/232*, 271/282* adv on a 112* LS I put a 1.6 rocker on the intake and a 1.5 rocker on the exhaust.

The heads are 180 CC Dart Pro 1 Platinums, with an advertised 64 CC chamber. The intake runners actually CC'd at 191 CC and the combustion chamber was 69 CC. Having paid a premium for the Pro 1 Platinum Heads, I expected the statedvolumes to be accurate vs the measured volumes. Oh well, don't cheap out, buy premium parts, from a reputable manufacturer, and you get what you pay for, right?

The combustion chambers have been milled to 65 CC. The intakes flowed 253 CFM @ .500", and exhaust flowed 203 CFM @ .500" lift. The low lift flow numbers weren't bad. If I can find the flow sheet, I'll post it.

My plan is to finish assembling the engine: cam, lifters, heads, intake, tin, etc. on Saturday, and drop it on Sunday. Not sure what intake I'm going to run on it. I'm torn between an old C4B, a GM #461 327/350 HP Chevelle intake, and a Weiand #8120 low-rise dual plane. I like the C4B for a nostalgia look, but mine has several stripped threads. The C4B and the #461 both let me run an oil fill tube, which in turn will let me run closed valve covers (I vented the block last time I had it in the Vette). On the other hand, the Weiand #8120 is a pretty decent piece and only gave up 1 MPH vs a Weiand high-rise Airstrike dual plane (which doesn't fit under the stock hood).

If all goes well and the stars are aligned, I will be running it at Famoso on 11/22. I'm curious to see how an aluminum headed, roller-cammed stroker compares to the relatively gutless original engine.

EDIT: TO ADD CORRECT CAM SPECS.
Posted on: 2008/11/14 16:44
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bogus Re: Engine swap on the C1
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compares? I think the phrase "apples vs. oranges" will easily apply here.
Posted on: 2008/11/14 19:37
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jsup Re: Engine swap on the C1
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Those C1s are pretty cars. I think you'll notice a big difference..

Good luck

As for the complaints on the heads, did you mention it to Dart? If so, what did they say? They are pretty active on their own forum, perhaps you should post your disappointment there and see how they handle it. Give them a shot to fix it before throwing them down the stairs.

I still for the life of me don't understand why people get so wrapped up in flow numbers. We've seen first hand how one forum member put great flowing heads on top of the wrong rings and will likely wind up pulling the motor and rebuilding it. To worry about flow numbers in a vacuum and at the expense of everything else, is kinda silly. Just saying I simply don't get the fascination with this statistic as anything significantly relevant above and beyond all other aspects of the engine components. Now, if it's an issue of getting what you pay for, I completely agree, they should provide what you paid for. I will say, that in many industries, boat motors for example are +/- 10% of stated power, I don't know if these parts have such an industry accepted tolerance.

Next time someone brags about their heads flowing more than stated numbers, I'll point out they are a POS and out of stated spec.....

For the record, I didn't bother wasting my time or money flowing my heads as I don't care. I can tell you exactly what piston, rings, cyl wall finish, etc...
Posted on: 2008/11/14 21:35
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cuisinartvette Re: Engine swap on the C1
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Most do care as if they are gonna spend XXX amount they typically dont want to settle for "almost as good" as.

My suspicion is 90% of people who buy them never double check and hope the piece do what it says. Just as with any industry gotta do your homework. Even then you can get screwed like that guy with the CE I posted about the other day. Such is life.
Posted on: 2008/11/14 22:16
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jsup Re: Engine swap on the C1
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Quote:

cuisinartvette wrote:
Most do care as if they are gonna spend XXX amount they typically dont want to settle for "almost as good" as.

My suspicion is 90% of people who buy them never double check and hope the piece do what it says. Just as with any industry gotta do your homework. Even then you can get screwed like that guy with the CE I posted about the other day. Such is life.


I don't disagree. Like the example I used, do you know if there's an industry accepted tolerance? If I buy a boat motor rated at 300HP it could be anywhere between 270 and 330, and Mercury, Volvo can still call it 300 HP. For years Merc was on the high side, and OMC was on the low side. Is there a similar generally accepted tolerance for head volume and flow?

How far do we take it? Do we measure cams to ensure duration and lift is as advertised? Do we flow manifolds? Do we take 1.6 Rockers ad measure them for accuracy? At some point it becomes kinda ridiculous, no? Flow numbers are just as important of any of the aforementioned items, and people typically just slap in a cam without thought, right?

Second, if it really bothers him, he can send them back and demand a flow sheet with a new set, or get a refund.

Third, I don't think at the end of the day, it's going to amount to anything in terms of performance, isn't that the bottom line? If there is a generally accepted industry tolerance, and it's within that, I don't see a problem.

I've seen people say their heads flow "more than advertised" which is just as much of a problem, right? Out of spec is out of spec.

Getting what you pay for is important, I agree completely, just some perspective...
Posted on: 2008/11/14 22:25
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wesmigletz Re: Engine swap on the C1
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Bogus, we'll see. I have a finely calibrated SOTP meter. If I can make it to the track on the 22nd, we'll have definitive proof one way or the other. I'm in the 12s already, using the original #s matching (threw that out there for the NCRS types)block and heads. My heads were competition ported by Mike Stark at CFM performance, and I doubt much more could be gained from an OE Camel Hump head. I doubt the Darts will be that big of an improvement. I see the HR cam is the variable. It has less duration, but more lift. Both cams are on a 112* LS. That said, I don't expect to pick-up more than a couple of tenths.

JSUP, I'm not a Dart hater. Given the 11 CC variance from spec, I would have to think that is a tooling issue. I suspect the heads are larger than 180 CC by design. Since the heads are CNC machined, the heads would not have that kind of variance as a result of machining.

I didn't throw Dart down the stairs. I reported my situation with them. Simply put, the "part didn't match the print". It's not my job to do Dart's QC, and I have no interest in sending the heads back. They're finally going on my engine. As an aside, I'm friggin sick and tired of those making money off the automotive hobby not delivering what they claimed, thus my "you get what you pay for rant." Quite frankly, I do not believe that to be the case the majority of the time. It only applies when dealing with an honest person or entity.

I'm a big fan of small, efficient, ports. The quality and volume of flow matter. This engine won't be dyno'd, but it will be taken to the track. My car is fairly well sorted, and the proof will be in the MPH on my slip. The heads/cam will deliver or they won't. It's not a direct A-B test, but I know exactly how the low-rent parts performed, and that will serve as a comparative basis.

WRT, the ring issue, if the rings do not seal that would cause issues regardless of the head on top, be they new rings mis-matched to a cylinder's finish, or worn rings.
Posted on: 2008/11/14 22:27
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jsup Re: Engine swap on the C1
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http://www.dartheads.com/dartboard/showthread.php?p=2432#post2432

Took care of it for you. Didn't say you were a hater, and I didn't say you weren't right.

This is the second such complaint I've seen here about Dart, and I'd like to see their response.
Posted on: 2008/11/14 22:32
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Matatk Re: Engine swap on the C1
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Post some pics of this swap, I'd like to see it going in.

Matthew
Posted on: 2008/11/14 22:34
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jsup Re: Engine swap on the C1
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Quote:

wesmigletz wrote:

JSUP, I'm not a Dart hater. Given the 11 CC variance from spec, I would have to think that is a tooling issue. I suspect the heads are larger than 180 CC by design. Since the heads are CNC machined, the heads would not have that kind of variance as a result of machining.

I didn't throw Dart down the stairs. I reported my situation with them. Simply put, the "part didn't match the print". It's not my job to do Dart's QC, and I have no interest in sending the heads back. They're finally going on my engine. As an aside, I'm friggin sick and tired of those making money off the automotive hobby not delivering what they claimed, thus my "you get what you pay for rant." Quite frankly, I do not believe that to be the case the majority of the time. It only applies when dealing with an honest person or entity.

I'm a big fan of small, efficient, ports. The quality and volume of flow matter. This engine won't be dyno'd, but it will be taken to the track. My car is fairly well sorted, and the proof will be in the MPH on my slip. The heads/cam will deliver or they won't. It's not a direct A-B test, but I know exactly how the low-rent parts performed, and that will serve as a comparative basis.

WRT, the ring issue, if the rings do not seal that would cause issues regardless of the head on top, be they new rings mis-matched to a cylinder's finish, or worn rings.


Look, having an issue with a product or it's marketing does not make anyone a hater. Cite me.. and I didn't say YOU threw them down the stairs I was waiting for the onslaught from others...anticipatory strike.

I don't dis agree with any of that, other than what I suspect is the definition of "small efficient ports" sounds a bit like marketing to me. But that's neither here nor there. (so where is it?)

I think Dart should address the issue and I posted on their site to see their response.

I am in COMPLETE agreement with you in terms of "get what you pay for", and "advertising matching delivery".. Perhaps, and I don't know if there is, there is a good reason. Let's see what they say to the link and we can decide to accept it or not.

To my point on the ring issue I was simply pointing out this overwhelming compulsion people have with flow numbers, at the expense of understanding what is really important, more so than flow numbers, in their motor. It simply strikes me as, well, stupid to know all about flow numbers and nothing else about the important parts of your motor. I find it an interesting study in human nature to place such importance on one particular item neglecting everything else.
Posted on: 2008/11/14 22:37
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lltrevino Re: Engine swap on the C1
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lord nows, I am in a similar fight with another head manufacturer, also.

long story short, I bought a new a*r 195 set of heads, and used them 2 months, I put on about 2500 miles. Winter came, I decided i wanted to upgrade from a 355 to a 406 short block. I took my like new A*R heads, to a highly respected shop ( Kippley Engines), I set up a cnc port n polish. well long story short I had a couple of swiss cheese spots in my runners, from the "core shift" that was common with these heads. That same cnc program later has run 10+ same cylinder geads without a hiccup, and they must of ran 30 + prior to my set of heads. You know a cnc is going to the exact same spot, every time. This was all prior to the holy grail of the "el*m*nator". Now i contact A*R numerous times, and they stated"aware of problem, and problem has been corrected" , however my problem is my own fault. I than last week asked a A*R engineer about my Dilema, and here was his response "

"That's kinda what I thought went down from reading a little of what you posted.

Consider this.....what if the place your head broke thru was always say .040 thick on most of the other castings....none of them would break thru but ALL of them would be extremely thin and long term reliability would always be an issue.

We guarantee our heads with our CNC work because we go thru all the extra trouble to cut our heads like a loaf of bread and make sure we have plenty of aluminum around our port walls based on the shape we CNC into the head (the water jackets are designed around our port designs....not someone else's)

AFR can not be responsible for another shops CNC program that obviously removes alot more material than we do in certain areas. It was up to them to do all the behind the scenes homework that we have invested in our own program (concerning verifying proper wall thickness) and they should have stepped up to the plate and offered you another one of their CNC castings in the event they couldn't weld/repair the one THEIR program broke thru.

That's what we would have done had you purchased our CNC program and had a problem with a port breaking thru into water. You should vent your frustration to the shop that did the CNC work.

How can you reasonably expect us to guarantee someone else's porting work....its no different than if someone buys our heads and grinds on them by hand poking a hole thru one of the ports. In that same situation would you expect AFR to eat the cost of a head and all the machine work involved?? Then think for a minute whats really different in your situation....just because they CNC'ed the same program before doesn't mean it was always right and the bottom line is with most products that you purchase, both performance related and anything else for that matter....if you modify it and have a problem you own it. You relinquish the right to return or warranty it....especially if what you modified created the problem.

What I would be willing to do just to try and help is to see if I can fix it for you and charge you a nominal fee to do so (basically do the work at cost). Perhaps we can repair them but of course I cant make you any promises.

Honestly though, the real company that needs to step up here is the company that did the CNC work. If you conducted a poll and shared this situation with everyone, I bet 75% plus would agree with what I'm saying....maybe more.

We are a stand up company and will warranty anything that we feel is remotely our fault....even gray area's that occasionally come up we stand behind, but this clearly is not a warranty with our company....the real warranty lies with the company that you paid to port your heads. I hope one day you step back and can see and understand that more clearly.

I would like to see if we can fix the heads....contact me next week if your interested in pursuing that.

Thanks,
Tony
661-705-8508



Quote:
Originally Posted by lltrevino
I took my pill, to be respectable here, but here is a real short. these heads were just prior to eliminator release. I will gather receipts, and extra. first we are talking cnc porting, done by Kippley engines, in WI. I am sure Tony has heard of Kippley. I bought heads from Nickerson Engines BRAND NEW. ran heads for UNDER 2500 miles on a stout 355, than over winter, got a deal on a 406 short block, had headS cnc ported, SAME PROGRAM USED ON 30 + SETS OF AFR HEADS. went through on 2 water jackets, 1 hole is unrepairable,. Tony you know bout cnc machines, they go same place, same time, rest assured cnc machine was not crashed, not wrong with program either, did at least 10 sets afterwards, no problems. HOWEVER 2 MONTHS PRIOR, Kippley has a similar problem, core shift. I not trying to be an ahole here, however my money is as green as yours, and having 1100.00 in a set of heads that are junk, really pisses me off. I have the email responses, and was in contact with sustomer service. WILL NOT ACCEPT A RETURN!!! how is this fair to me?
Quote:
Originally Posted by Tony Mamo @ AFR
Mike,

I have not ignored this customer. Ignoring implies there has been an effort made to communicate with me and this customer has not PM'ed me, nor has he picked up the phone in an attempt to contact me either. I make myself available to everyone.

The only thing I know about this situation is from what I have briefly read (and Im a little gray on this) which involves the fact this customer modified our castings by having someone else port them (and I believe broke into a water jacket which he now blames us for). This type of work obviously nullifies any warranty AFR can offer which would be standard procedure for anybody's product (if I buy a Dart block and grind and modify it to the point it creates a problem I wouldn't expect Dart to warranty to the block because it was my fault for modifying it in the first place....just an example of the point I am making)

That said I would like to hear the specific details of what actually went down and I encourage thic customer to contact me directly. I would like to try and work something out in an attempt to make peace but without knowing exactly what Im dealing with its hard to say what AFR may or may not be willing to do to help out.

My phone is 661-705-8508 or a PM would also be fine but I prefer we speak on the phone at this point.

Thanks,
Tony


Quote:
Originally Posted by Iron Chef
I will send your PM directly to Tony.

Tony: Please handle things with this gentleman and include me in your correspondence. If you need an Email, I can provide one. Per forum rules, if this cannot be resolved between you two, he will be entitled to start a thread about it.

Thanks,

Mike
Iron Chef
Moderator


Quote:
Originally Posted by lltrevino
I AM IN NO WAY TRYING TO PICK A FIGHT, FIRST OFF!!! however, according to a post I just read, people come to this forum to read, and write about experiences with a said vendor. My question is, how do I share the information of a vendor selling an 1100 dollar product, that has flawed castings? I have a set of 2 month od, at the time) core-shifted afr heads ( common problem), that when I contacted customer service @ AFR, I was advised, " AFR was stopping flawed castings from reaching the consumer" . however AFR was not doing anything for the consumer, whom already has this product, whom lost 1100.00?????? every time I talk with Tony, I am ignored, just enhances my point further, dont you think???z well let me know, however I am not looking for a suspension or ban, however I want to share my $1,100+experience!!!!! "
Posted on: 2008/11/15 4:18
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jsup Re: Engine swap on the C1
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So are you banned yet? Tony call out the dogs on you? Funny he has insight on all the subject related bannings.
Posted on: 2008/11/15 4:33
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jsup Re: Engine swap on the C1
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Honestly though, the real company that needs to step up here is the company that did the CNC work. If you conducted a poll and shared this situation with everyone, I bet 75% plus would agree with what I'm saying....maybe more.


That's rich.....on that forum I betcha the results are 99%. I think that part is pathetic.

Now, I have a question...I do see Tony's point, why do you think it's invalid?

Can you explain how he's not right, I'd take his position too if it were me, seems like a fair answer.

Are you saying that the only reason the heads were damaged is because the casting shifted, not because the CNC was bad?

Is it the point that they knew about the core shifting and the heads should be replaced because of that known problem and demonstrated that you had the problem regardless of what the machine shop did. If that is your position, then I agree.
Posted on: 2008/11/15 4:39
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lltrevino Re: Engine swap on the C1
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No matter what would of happened,I would notbe able to port these heads. The porting shop, waived the 600.00 fee, obviously. The PORTING SHOP than got me a reasonable comparing head, for a killer deal.
My castings were flawed, since they were manufactured. This was common, after I did some research. I did get one hole repaired, however The other hole, is in a spot were only jb weld could be applied. No angle for a tig welder, I am a certified, mig / tig welder, trust me , if there was any chance, I would do it. Same fixture, machine, and program, produced many, many good heads, the water jackets, being shifted was a notorious problem, 3 years ago. One would be amazed, how many bad sets of heads are out there. I have read at least 5 others, with the same problem. I mean, I think, since the castings were acknowledged, to have been problematic, by there own customer service reps, there should be something for the consumer here. Heck, I would settle for a good discount. I think there action of correcting the manufacturing problem, than there lack of action of correcting the consumer that had the defective products, would hurt there sells. however, I guess, with as many of bad heads out there, of this design, this company would of went belly-up, and never released , by there definition, "holy grail" eliminator series.
by the way,the last I checked, I still had a function account over there, FOR NOW.
Posted on: 2008/11/15 5:29
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wesmigletz Re: Engine swap on the C1
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lltrevino, sorry to hear about your head problems. Coreshift can be a bitch. My OE heads had some as well.

I imagine most manufacturers would be hesitant to work with you once some grinding has been done on their heads, by hand or a CNC program. I think your best bet is to work with Tony if you're in direct conversation with him... I'd give him a chance to look at it and see what he can do for you.

Good luck with getting it resolved.

Wes
Posted on: 2008/11/15 6:47
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cuisinartvette Re: Engine swap on the C1
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I dont see how a mfr will ever take responsibility for the actions of someone else modifying their product.

Shop never sonic checked the walls beforehand?

its my opinion anyone with a CNC has to allow for some type of variance regardless. A "take it to the limit" CNC program is only asking for problems imo.
Bad situation all the way around.
Posted on: 2008/11/15 7:06
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jsup Re: Engine swap on the C1
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Quote:

cuisinartvette wrote:
I dont see how a mfr will ever take responsibility for the actions of someone else modifying their product.

Shop never sonic checked the walls beforehand?

its my opinion anyone with a CNC has to allow for some type of variance regardless. A "take it to the limit" CNC program is only asking for problems imo.
Bad situation all the way around.


I think his point is that, agree with it or not, that 30 sets of heads were run with no problem.

His had a core shift problem that the CNC simply exposed.

That the heads should be replaced because of the core shift problem regardless how i was discovered. On that basis, he does have a strong point.

If a product has a KNOWN underlying flaw, regardless of the method of discovery, it is incumbent on the manufacturer to make it right. It's not as if this is the only set that ever core shifted.

I understand AFR's point, I'd make the same one, but after consideration, and a night's sleep, if the problem was known to the manufacturer, regardless how he found out, it should be replaced. Their position has no merit.


There are really two core issues at hand here:

1.If the core shift was discovered BEFORE the CNC was put to it would anyone argue that it shouldn't be replaced? No, that would be silly. It would be a defective product. This is NOT about breaking through the wall of the cyl with a CNC, it's about core shift.

2. The other question needs to be asked is did the CNC CAUSE the core shift. I have not heard that argument, and that would be hard to make.

In my court, I'd rule for the plaintiff, replace the fkn head you cheap bastard. This was a known problem with many heads, no one has argued that core shift hasn't happened. The argument made by AFR is a straw horse. It has nothing to do with the core sift condition that existed before the head was put on a machine.

The ONLY question is was there core shift or not, seems to be proven there was. End of story.
Posted on: 2008/11/15 14:43
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Matatk Re: Engine swap on the C1
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jsup wrote:


In my court, I'd rule for the plaintiff, replace the fkn head you cheap bastard. This was a known problem with many heads, no one has argued that core shift hasn't happened. The argument made by AFR is a straw horse. It has nothing to do with the core sift condition that existed before the head was put on a machine.



Good thing you're not a judge, then.

Unfortunately, the heads were poked through by the aftermarket cnc process. However, AFR delivered a product that in stock form performed as it was intended. Just because someone attempted to change the stock qualities and it was damaged, that's the consumer's (and shop's) fault. If you bored out an engine block oversized and it went through the cylinder wall, is that chevy's fault? Nope. They provided a product that worked as intended.

Now that being said, do I think it's unfortunate? Yes. I think if AFR wanted to offer a set of heads at cost, that would be a stand up thing. But they are not responsible for someone else making changes to their design.

Larry - what heads, if you don't mind, did you end up going with for the second round?

Matthew
Posted on: 2008/11/15 15:02
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jsup Re: Engine swap on the C1
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Quote:

Matatk wrote:
Quote:

jsup wrote:


In my court, I'd rule for the plaintiff, replace the fkn head you cheap bastard. This was a known problem with many heads, no one has argued that core shift hasn't happened. The argument made by AFR is a straw horse. It has nothing to do with the core sift condition that existed before the head was put on a machine.



Good thing you're not a judge, then.

Unfortunately, the heads were poked through by the aftermarket cnc process. However, AFR delivered a product that in stock form performed as it was intended. Just because someone attempted to change the stock qualities and it was damaged, that's the consumer's (and shop's) fault. If you bored out an engine block oversized and it went through the cylinder wall, is that chevy's fault? Nope. They provided a product that worked as intended.

Now that being said, do I think it's unfortunate? Yes. I think if AFR wanted to offer a set of heads at cost, that would be a stand up thing. But they are not responsible for someone else making changes to their design.

Larry - what heads, if you don't mind, did you end up going with for the second round?

Matthew


Ok, I'll try again.

I am not arguing that the CNC didn't expose the problem.

Here's the question.....

The problem existed before the CNC touched it right? At that point it should have been replaced, right?

Did the CNC cause the problem? I haven't seen that argument. The CNC caused A problem, but the at isn't what rendered it worthless. It was the core shift that made them useless before the CNC touched them.

You skipped over the core issue here of weather or not core shift existed, regardless of the discovery. It's the core shift that made the heads worthless, not the CNCing. Or do you think I'm wrong?

I mean is it standard practice to have to check for core shift and they didn't? I don't know that answer.

I do understand the point of how it was discovered, and initially bought into it.
Posted on: 2008/11/15 15:16
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cuisinartvette Re: Engine swap on the C1
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Where is all this talk about other heads with core shift, Ive never seen it . There was some issue with a batch of valves a number of years ago with some older castings and them making announcements on various forums they would take care of things gratis. Dont remember all the details but do recall reading the threads.
Posted on: 2008/11/15 15:22
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jsup Re: Engine swap on the C1
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cuisinartvette wrote:
Where is all this talk about other heads with core shift, Ive never seen it . There was some issue with a batch of valves a number of years ago with some older castings and them making announcements on various forums they would take care of things gratis. Dont remember all the details but do recall reading the threads.


I am going on the information he posted. He states there was a run of core shift heads. Is this true? I do remember Tony referring to "past casting problems"...is this what he refers to or was it the oil issue?
Posted on: 2008/11/15 15:28
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cuisinartvette Re: Engine swap on the C1
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I think it was either a oil drainback or puddling issue. He would be the guy to ask that.
Posted on: 2008/11/15 15:37
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jsup Re: Engine swap on the C1
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So was there a core shift run that was pulled or not?

Anyone? Anyone?

If there was, that's one issue, if this is an isolated case, that's another.
Posted on: 2008/11/15 15:41
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Matatk Re: Engine swap on the C1
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I think this hijack deserves its own post, not taking over Wes'.

Wes, post those pics when you're done, bro!

Matthew
Posted on: 2008/11/15 15:41
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cuisinartvette Re: Engine swap on the C1
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jsup wrote:
So was there a core shift run that was pulled or not?

Anyone? Anyone?

.


no.

IMO if you buy heads from XX manufacurer and want to cut on them then who better to do it than the maker themselves. That way if something happens its their baby.

Back to Wes....
Posted on: 2008/11/15 15:43
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jsup Re: Engine swap on the C1
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http://www.dartheads.com/dartboard/sh ... ?p=2445&posted=1#post2445

Interesting response.....I'm sure next week when people come back to work there will be more.

I asked for clarification in my follow up post.
Posted on: 2008/11/16 6:08
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wesmigletz Re: Engine swap on the C1
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JSUP, the guy who responded mentioned a 332 going 10.70s with 291 heads. Not particularly impressive for a race car.

Our car's a street car, and was driven cross-country, raced at Beechbend, and drove back, without missing a beat. My car is what it is... a dished-pistoned, 3.36 geared, 1800 stall 12 second street car, that idles with 18" of vacuum at 800 RPM and has no problem with the LA traffic during my 3 hour round-trip work commute.

With more compression, more cam, and more stall, I'd be in the 10s too... that's not what I want. I'm going to stay naturally aspirated, so that pretty much leaves heads and a roller cam as my best options...

BTW, the Dart 180 heads were not purchased for the Vette, I got them for my 72 Truck's 383 this past December. I'm putting the 383 in the Vette for a while to keep it on the road.

It will be this engine's second time to go in the Vette... I swap engines like CFOT changes their underwear.

I pulled it out of the truck two years ago, and put it in the Vette to make the anti-tour. Since then, I re-ringed the 383. I added the Engle HR cam and Dart heads today. I'll drop it tomorrow, and barring the unexpected, I'll be driving it tomorrow.

BTW, I posted the flow numbers, but I wasn't complaining about them. My dissatisfaction was with the actual size of the runners and the chambers.
Posted on: 2008/11/16 6:55
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bogus Re: Engine swap on the C1
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Gee... you do swap motors on a regular basis...

Can't wait to hear the outcome!
Posted on: 2008/11/16 7:36
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cuisinartvette Re: Engine swap on the C1
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[QUOTE]JSUP, the guy who responded mentioned a 332 going 10.70s with 291 heads. Not particularly impressive for a race car. [/QUOTE]

Wes, sounds like Butch (trmnatr)from T.C, wanna bet thats his 406?
Posted on: 2008/11/16 7:44
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jsup Re: Engine swap on the C1
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wesmigletz wrote:

BTW, I posted the flow numbers, but I wasn't complaining about them. My dissatisfaction was with the actual size of the runners and the chambers.


He was just a poster, I want to hear Dart's position how 180 heads are actually 190 and how that is or isn't within factory spec. And the chambers were off.

That was the core issue, wasn't it?

Seems there's a discrepancy and the manufacturer should explain it, no?

That's why I posted a follow up explaining exactly that.
Posted on: 2008/11/16 13:19
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cuisinartvette Re: Engine swap on the C1
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IMO the explanation is a little disappointing.

"They are as cast so it can be off that much". BS.
2, 3, maybe 5? 11?? Thats a lot.

How come its not off by 11 cc from port to port?

Or just advertise it as a 190 cc head.

I got nothing against Dart (heck, I got a set on mine too) at all but how do you excuse a difference that big? I was really hoping for something we could all learn from as Dartvader is obvously a very intelligent guy and knows his heads.
Posted on: 2008/11/18 5:26
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88BlackZ51 Re: Engine swap on the C1
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Since Jsup is at cylinder heads once again, I thought I would mention something. What's this tolerance crap? Cylinder heads are not like boat motors, or like shock absorbers. Those heads imo aren't even close to what the manufacturer claims, but I am not suprised to say the least. It's funny how both of my AFR's were right on the money dude. Building motors are not cheap, Dart has to have some accountability especially when ppl are building there motors around port size, cfm etc....When I order something and pay good money, I am not thinking about tolerances. This is why I went with company that double checks things, and customer service is excellent.
Posted on: 2008/11/18 18:02
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jsup Re: Engine swap on the C1
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88BlackZ51 wrote:
Since Jsup is at cylinder heads once again, I thought I would mention something. What's this tolerance crap? Cylinder heads are not like boat motors, or like shock absorbers. Those heads imo aren't even close to what the manufacturer claims, but I am not suprised to say the least. It's funny how both of my AFR's were right on the money dude. Building motors are not cheap, Dart has to have some accountability especially when ppl are building there motors around port size, cfm etc....When I order something and pay good money, I am not thinking about tolerances. This is why I went with company that double checks things, and customer service is excellent.


Everything manufactured has a tolerance. I asked what was acceptable, and I expect dart to be held to the same same standard if they want my money.

As far as double checks things and so forth, don't be so sure. There are plenty of people that have received sub standard QC heads from AFR too. One mod right here on this forum. All manufactures do it. Get off it.

I didn't get on the cyl head thing, just so you know. Wes said he had a problem, I hepled by asking Dart for their position and asking a reasonable problem. Then you come in with this unrealted cheerleader bullshit. I didn't see anyone ask you how wonderful your AFRs are, no one mentioned AFR so how about you STFU and stop making this AFR is the greatest product in the world and everything else sucks, Like you always do. Is there any topic in the world that can be discussed without you talking about your dam heads? Seek help man.
Posted on: 2008/11/18 18:14
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jsup Re: Engine swap on the C1
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cuisinartvette wrote:
IMO the explanation is a little disappointing.

"They are as cast so it can be off that much". BS.
2, 3, maybe 5? 11?? Thats a lot.

How come its not off by 11 cc from port to port?

Or just advertise it as a 190 cc head.

I got nothing against Dart (heck, I got a set on mine too) at all but how do you excuse a difference that big? I was really hoping for something we could all learn from as Dartvader is obvously a very intelligent guy and knows his heads.


Like I said, they will post a response, and people can accept it or not.
Posted on: 2008/11/18 18:17
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cuisinartvette Re: Engine swap on the C1
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[QUOTE]Is there any topic in the world that can be discussed without you talking about your dam heads? Seek help man.[/QUOTE]
No


Stock stuff has the same issues also, anythign manufacutred I bet. I was going through a set of GM runners last night and noticed one was .15 bigger than the other 7. Oh well.
Posted on: 2008/11/18 18:18
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jsup Re: Engine swap on the C1
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cuisinartvette wrote:
[QUOTE]Is there any topic in the world that can be discussed without you talking about your dam heads? Seek help man.[/QUOTE]
No


Stock stuff has the same issues also, anythign manufacutred I bet. I was going through a set of GM runners last night and noticed one was .15 bigger than the other 7. Oh well.


Serious CV be honest, did you see any redeeming value in Ricky's post other than to stir shit?

No one asked about his heads, AFR, or anything else. The scope of this conversation was very narrow and did not include anything related to his compulsive leg humping.

And I get the reputation, go figure.
Posted on: 2008/11/18 18:25
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cuisinartvette Re: Engine swap on the C1
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Hes just proud of his parts, thats all.
Cracks me up though at just the sight of him posting turns you upside down. I keep getting an image of a dog going ballistic and barking at a cat on the other side of a block wall. Dont know why I find it funny but I do.
Posted on: 2008/11/18 18:29
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jsup Re: Engine swap on the C1
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cuisinartvette wrote:
Hes just proud of his parts, thats all.


OK, fine....but to keep going on and on and on about how everything else is second rate demonstrates clear ignorance. The criteria he uses is questionable at best.

Quote:

Cracks me up though at just the sight of him posting turns you upside down. I keep getting an image of a dog going ballistic and barking at a cat on the other side of a block wall. Dont know why I find it funny but I do.


True, I'll tell you why, he's spreading lies and making connections that don't exist. He's talking out of his ass. That's why.
Posted on: 2008/11/18 18:42
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88BlackZ51 Re: Engine swap on the C1
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cuisinartvette wrote:
Hes just proud of his parts, thats all.
Cracks me up though at just the sight of him posting turns you upside down. I keep getting an image of a dog going ballistic and barking at a cat on the other side of a block wall. Dont know why I find it funny but I do.


Because it is funny. When this dude see's 3 letters with the middle letter being F, he goes into a rage.

I know all about the moderator's heads, which is nothing compared to those dart's. I bet his heads are "almost" if not exactly what AFR says they are in regards to intake port, and combustion chamber, two major things.

Remember I have been talking to members like him long before you joined. I know all about his street ports, and how much he paid for them, because I setup the price! :lol:

But guess what my street ports measured 65-66cc across the board. Guess what they were advertised as? 65cc!

Go figure!
Posted on: 2008/11/19 19:37
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BeachBum Re: Engine swap on the C1
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lltrevino wrote:
You know a cnc is going to the exact same spot, every time.



The only thing I will add to this dilema is that the above statement is very far from the truth.... there are so many variables with a CNC machine that its incredible..... Operator error is by far and away the most common mistake made on a CNC machine. In addition, most CNC machines have a considerably amount of positioning error in them as they sit.

In the metalworking industry, there is a certain amount of scrap that is tolerated and actually built into the quoting they do. The scrap is generated by a wide variety of means, but all have to do with the CNC machine not doing what they were hoping it was going to do. In your situation, its sounds like the program itself is okay considering it has run other same brand cylinder heads successful, but keep in the G-code program they utilize for the path is simply just that, a programmed tool path. But, then a lot of good things have to happen for the CNC machine to actually follow that path.

The most common operator error is the loading of the offsets, you have multiple offsets for most CNC programs, in the case of a cylinder head, it can literally be a dozen or more. Starting with the correct tool offset, the operator has to touch the tool off and then load that length offset into the tool table either manually or automatically. Then they have to remember to enter in the tool radius. If the tool was previously set-up, has anybody changed that tool in the tool changer? and if yes, did they accidently put in the wrong tool in either length or diameter.... for example, a very, very common mistake is for the operator to change a worn out tool in the ATC, and puts in the correct type of mill such as an end-mill, but doesn't notice that he put in a 3/8" diameter tool rather than a 1/4"..... which means he has to manually change that diameter in the tool table after he touches off for the tool length, if he forgets, then the entire cnc program will be off by that amount, Ie meaning, the cut is too deep or too shallow.

Same goes with the work offsets, the corner of that cylinder head may be one offset, then the actually corner entry into the port may be another... they have to call the correct work zero offsets and hope they were correctly entered in the first time. Unless they have the perfect part fixtures, these will change from cylinder head to cylinder head..... and regardless, they should be reset for each cylinder head anyway, which requires the operator to re-touch off or probe the corners. To give you an example of what happens when a work offset is off, the path will be shifted over the value of the offset error, meaning, typically you will cut too deep on one side of the port, and you'll cut air on the other side.

What makes this that much more difficult, on a cylinder head, the cnc program is typically not one long part program based upon one offset, but instead, they'll do a port, step over, call the new offset, and then repeat the program, which is typically a subroutine they are calling. When using this method, an indication that an individual offset for a port was off is that one port is clearly damaged, but the others appear to be generally okay. (The good news about a work offset, is that if the machine has a good home reference, each offset is un-related to the other, thus you do not have a domino effect.)

There are many, many other operator errors that can and do damage parts everyday, plus there are many CNC machine set-up parameters & compensation that must be set-up correctly or the machine will not be acurate. In fact, most CNC machines utilize a rotary encoder for positional feedback, this alone is a big problem considering 90%+ of these are directly mounted on the Servo Motor..... thus, it does not take backlash, screw error or cross compensation into effect.... it instead reports the position of the axes as per the motor vs the actual table position. The more expensive option of Linear Encoders will vastly improve this situation, but due to the added expense, most CNC machining centers do not have them.

The above errors account for literally Billions of dollars in losses that are pretty much deemed acceptable every year to Manufacturers of all types of widgets..... just the nature of the game in the machining business. CNC manufacturers are constantly in competition with each other on how to make a CNC easier and more fool proof.... but alas, its always an uphill battle.

Having said that, with your particular situation, I have no idea what happened.... I'm just saying, keep an open mind and also do not for a second put your total faith in a CNC machine..... I think without a doubt the most common technical phone call that a CNC machine manufacturer receives from their customers is " Help !... my CNC machine will not repeat !"

Good luck with a decent resolution.
Posted on: 2008/11/20 18:06
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lltrevino Re: Engine swap on the C1
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Quote:

BeachBum wrote:
Quote:

lltrevino wrote:
You know a cnc is going to the exact same spot, every time.



The only thing I will add to this dilema is that the above statement is very far from the truth.... there are so many variables with a CNC machine that its incredible..... Operator error is by far and away the most common mistake made on a CNC machine. In addition, most CNC machines have a considerably amount of positioning error in them as they sit.

In the metalworking industry, there is a certain amount of scrap that is tolerated and actually built into the quoting they do. The scrap is generated by a wide variety of means, but all have to do with the CNC machine not doing what they were hoping it was going to do. In your situation, its sounds like the program itself is okay considering it has run other same brand cylinder heads successful, but keep in the G-code program they utilize for the path is simply just that, a programmed tool path. But, then a lot of good things have to happen for the CNC machine to actually follow that path.

The most common operator error is the loading of the offsets, you have multiple offsets for most CNC programs, in the case of a cylinder head, it can literally be a dozen or more. Starting with the correct tool offset, the operator has to touch the tool off and then load that length offset into the tool table either manually or automatically. Then they have to remember to enter in the tool radius. If the tool was previously set-up, has anybody changed that tool in the tool changer? and if yes, did they accidently put in the wrong tool in either length or diameter.... for example, a very, very common mistake is for the operator to change a worn out tool in the ATC, and puts in the correct type of mill such as an end-mill, but doesn't notice that he put in a 3/8" diameter tool rather than a 1/4"..... which means he has to manually change that diameter in the tool table after he touches off for the tool length, if he forgets, then the entire cnc program will be off by that amount, Ie meaning, the cut is too deep or too shallow.

Same goes with the work offsets, the corner of that cylinder head may be one offset, then the actually corner entry into the port may be another... they have to call the correct work zero offsets and hope they were correctly entered in the first time. Unless they have the perfect part fixtures, these will change from cylinder head to cylinder head..... and regardless, they should be reset for each cylinder head anyway, which requires the operator to re-touch off or probe the corners. To give you an example of what happens when a work offset is off, the path will be shifted over the value of the offset error, meaning, typically you will cut too deep on one side of the port, and you'll cut air on the other side.

What makes this that much more difficult, on a cylinder head, the cnc program is typically not one long part program based upon one offset, but instead, they'll do a port, step over, call the new offset, and then repeat the program, which is typically a subroutine they are calling. When using this method, an indication that an individual offset for a port was off is that one port is clearly damaged, but the others appear to be generally okay. (The good news about a work offset, is that if the machine has a good home reference, each offset is un-related to the other, thus you do not have a domino effect.)

There are many, many other operator errors that can and do damage parts everyday, plus there are many CNC machine set-up parameters & compensation that must be set-up correctly or the machine will not be acurate. In fact, most CNC machines utilize a rotary encoder for positional feedback, this alone is a big problem considering 90%+ of these are directly mounted on the Servo Motor..... thus, it does not take backlash, screw error or cross compensation into effect.... it instead reports the position of the axes as per the motor vs the actual table position. The more expensive option of Linear Encoders will vastly improve this situation, but due to the added expense, most CNC machining centers do not have them.



The above errors account for literally Billions of dollars in losses that are pretty much deemed acceptable every year to Manufacturers of all types of widgets..... just the nature of the game in the machining business. CNC manufacturers are constantly in competition with each other on how to make a CNC easier and more fool proof.... but alas, its always an uphill battle.

Having said that, with your particular situation, I have no idea what happened.... I'm just saying, keep an open mind and also do not for a second put your total faith in a CNC machine..... I think without a doubt the most common technical phone call that a CNC machine manufacturer receives from their customers is " Help !... my CNC machine will not repeat !"

Good luck with a decent resolution.


In part i absolutely agree with your post. However, I am adding an attatchment of a screenshot, form another forum , on March, 2007. This is a response to a post, with an individual, with a similiar problem as mine. Please note the response to the quote. I think this speak volumes, on the case, the MFG was quite well aware of a problem, And they do not care about the consumer. Instead, my interpetation is, come and purchase another set of our newly redesigned, hoping not to have any more problem product.
I bought a set of new cylinder heads, used for 2500 miles, and people are treating this like an 1100 dollar set of spark plugs. Hey try a new set of plugs.

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jpg  afr3.jpg (182.86 KB)
1801_492ac33a537d3.jpg 1024X768 px
Posted on: 2008/11/24 15:11
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BeachBum Re: Engine swap on the C1
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You know I understand your pain.... I really do. And things like what happened to yours happen all the time, not just with AFR cylinder heads, but every type of cylinder head. Hence, why many of those cylinder head porters have acquired impressive welding skills as well. In fact, many times the customer never knows about it, they drop off the cylinder heads and then pick them up a week or two later..... the problem with yours, apparently 1 or 2 of the holes were too deep to be repaired. If they weren't, you probably would have never known they even broke through to begin with..... they would have repaired and cleaned them up and given them back. That is bad luck ! But, I will say, your cylinder head porter should have caught the problem way before they made a cut….. what is the old adage ?.... measure twice, cut once. They really needed to touch off or probe a few known positions on that cylinder head before plunging a cutter into it.

In addition, if your cylinder heads had serious core shift, they should have known 2 seconds after that cutter hit the material that something was wrong and stopped the CNC program. Most qualified CNC machinist, when first starting a program will have one hand on the feedrate override and other hand on e-stop, thus when that cutter hits the material if there is the slightest of problem such as not cutting anything but air, or a much too heavy cut….. an experienced cnc machinist will know this literally a second into the cutter path and will stop the CNC program dead in its track. They can even typically analyze the chip itself and make adjustments on the spindle speed and/or axes feedrate to create a better cut/chip. In addition, at the very, very least after doing the first port, they needed to do a program stop and then inspect the material with the very least a dial indicator as well as inspect the cutter itself. If everything was A-okay, then let the program stepover and repeat, stop again and test……. To be honest, even if your cylinder heads looked like a crooked building, the machining never should have gotten past the 1st port. You just don’t slap on somebody’s expensive cylinder heads, press cycle start and go get a cup of coffee…… unless you are careless.

But, at the end of the day, the reality of it is, a cylinder head manufacturer is selling you a cylinder head that is based upon the chamber size they advertised, flow numbers & runner size..... and of course they need to be able to bolt-up and seal. After that, no cylinder head manufacturer can guarantee a cylinder head porters program will work with the given cylinder head..... they have no idea where and how the G-code tool path was created in the first place, it would be impossible for them to guarantee everybody’s porting program won't break through. Not to mention the skill level of the CNC machinist. Its hard for me to explain this, but it is reality....

But, my personal conclusion is that if your cylinder heads are so severely shifted that the heads won’t seal or even match-up to the intake or the chamber size or runner size are beyond advertised or they do not flow what is advertised, then that would be AFR’s fault !! But, if somebody cuts a bunch of holes in these cylinder heads, regardless of anything else, that is the fault of the person doing the cutting….

Good Luck !
Posted on: 2008/11/24 20:51
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jsup Re: Engine swap on the C1
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hey beach bum, lots of good points. Do you think that a core sift problem is a re-call type issue? Given the clear recognition of the problem by the manufacturer, should those pieces be recalled? Do all heads do this?
Posted on: 2008/11/24 21:25
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BeachBum Re: Engine swap on the C1
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jsup wrote:
hey beach bum, lots of good points. Do you think that a core sift problem is a re-call type issue? Given the clear recognition of the problem by the manufacturer, should those pieces be recalled? Do all heads do this?


Thats a good question !

But, I don't have an answer.... I think thats a better question for the people in the industry. But, I would "guess" it has to do with the how much shift and what are the implications of the shift.

If it won't seal, then definitely, a recall/refund/exchange policy of some sort would be the appropriate thing to do considering you're risking damaging your motor considering we know coolant and oil make a great milkshake, but a lousy lubricant.

I'm not defending Tony, he's on his own, with all I know the set of cylinder heads in question started life as boat anchors.... he has to solve these types of problems on his own.

But, I will say from the CNC machining point of view, if the cylinder heads had a serious problem, this should have been recognized immediately by the porter.
Posted on: 2008/11/24 21:46
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jsup Re: Engine swap on the C1
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That's a fair response. I wonder if shift is typical and if there is an industry accepted tolerance for it, and what that is.

see, I think I am taking a position that the CNC simply exposed the problem, but the problem was a manufacturer defect and should be replaced. Was the tech running the machine slopply, sure, but was that the problem?

Is your position that if the machine was stopped 10 minutes earlier things would be different? Yes, he'd have an undamaged useless head, now what? I don't see how that makes a difference, when does a defect become a defect? (sounds like abortion huh) A factory defect becomes a factory defect when it leaves the factory, at conception.

The mechanism by which it is discovered is irrelevant. But that goes back to my last question...is this a recall type issue? and Is there an industry accepted amount of shift, if so, what is it, and are these out of industry accepted spec? If so, lltrevino has a valid point, if not, then it changes.

Try this.....you buy a tire, it vibrates all the time, you hit a curb. You find out that the tire's belts were shifted from the factory causing not only the vibration, but the accident as well.

Does the tire manufacturer owe you new tires or does the manufacturer tell you to buy more of his twice the price tires since they don't have the belt shifting problem? note, he never denied there was a belt shifting problem.
Posted on: 2008/11/24 23:31
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BeachBum Re: Engine swap on the C1
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Quote:

jsup wrote:
That's a fair response. I wonder if shift is typical and if there is an industry accepted tolerance for it, and what that is.

see, I think I am taking a position that the CNC simply exposed the problem, but the problem was a manufacturer defect and should be replaced. Was the tech running the machine slopply, sure, but was that the problem?

Is your position that if the machine was stopped 10 minutes earlier things would be different? Yes, he'd have an undamaged useless head, now what? I don't see how that makes a difference, when does a defect become a defect? (sounds like abortion huh) A factory defect becomes a factory defect when it leaves the factory, at conception.

The mechanism by which it is discovered is irrelevant. But that goes back to my last question...is this a recall type issue? and Is there an industry accepted amount of shift, if so, what is it, and are these out of industry accepted spec? If so, lltrevino has a valid point, if not, then it changes.

Try this.....you buy a tire, it vibrates all the time, you hit a curb. You find out that the tire's belts were shifted from the factory causing not only the vibration, but the accident as well.

Does the tire manufacturer owe you new tires or does the manufacturer tell you to buy more of his twice the price tires since they don't have the belt shifting problem? note, he never denied there was a belt shifting problem.


In response to your questions, on how typical is shift and what is the acceptable amount. I personally do not know the answer to either, but I have heard of shift many times over the years on a variety of cylinder heads, but to what degree and how much is accepted is beyond me. More typical, I also hear of breaking through the wall of the runner, usually by hand porting though, but thats only because most porters do not have 5 axes CNC capability due to the high cost.

In regards to who is at fault on the cylinder head breaking through on the porting, I do have a solid opinion on that, and that is the porters fault, simply because I have an acute understanding of the CNC process, as I teach it. But, I understand what you are saying, the cylinder head was bad, and now it has holes in it.... its still bad. But, this particular cylinder head was usuable as per the poster running it for 2500 miles, and I assume performed well on his original 350 considering I hadn't heard of a performance complaint, but do not know. Thus, what I am saying, he had a functional high performance cylinder head.... and now he doesn't. If it didn't perform from the get-go, it should have been brought to the attention of the manufacturer immediately, not after un-repairable holes had been made.

But, back on the porter breaking through, I can not emphasize enough, that a cylinder head porter has to pay attention to what they are doing and if the cutter is taking off too much material, stop the program and figure out why..... this really, really is CNC machining 101 and very, very common. In fact, I would say over 50% of CNC programs that are executed, are stopped before completion due to a variety of reasons, and then re-started once the problem is solved, with volume production applications being the exception.

Also, we have to consider, the manufacturer of the cylinder head knows nothing about the cnc program that is modifying its port and cannot reasonably warrantee anybody or everybody's cnc program. You have to understand, no two cylinder head porting programs are identical or even close to identical, and also no two cylinder heads are guaranteed to be identical for many reasons, (such as a new version of an existing cylinder head that may have made adjustments to the port that the porter did not, nor could have known about)

I also want to emphasize, in the manufacturing world, and you have to just trust me on this, that the vast majority of the scrap made is 100% directly related to human error.... its a big, big problem and goes back to setting the correct offsets, tool compensation and even machine error compensation in some cases.... plus all CNC machines have error. If they have good reliable Linear Encoders for positional feedback, the error will typically be 5 microns or less guaranteed per meter of travel, which is plenty sufficient for porting cylinder heads, but if they are rotary encoders on the motor, they will typically have considerable backlash error, cross compensation and screw wear error. All of these can be compensated by the CNC, but its on on-going project because all of those variables change with machine use.

But, the blame game really doesn't matter, at the end of the day, we have a fellow racer who has a set of cylinder heads with holes in them and I understand that is very disappointing.

I wish him good luck in finding a resolution.
Posted on: 2008/11/25 0:20
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jsup Re: Engine swap on the C1
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I think we're having 2 different conversations. I don't disagree with any of that, my point pre dates it getting on the CNC.

My question is....was the part defective when it left the warehouse? That really in my mind is the only question.

There does not seem to be an argument that there were other parts that were defective when they left the warehouse.... is this one of those?
Posted on: 2008/11/25 0:25
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BeachBum Re: Engine swap on the C1
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jsup wrote:
I think we're having 2 different conversations. I don't disagree with any of that, my point pre dates it getting on the CNC.

My question is....was the part defective when it left the warehouse? That really in my mind is the only question.

There does not seem to be an argument that there were other parts that were defective when they left the warehouse.... is this one of those?


I think, that if the poster purchased the cylinder head as new from the manufacturer and it was certifiably identified with a problem such as core shift, that it should be replaced under warranty at no-cost.... that would be my opinion on that....
Posted on: 2008/11/25 0:43
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jsup Re: Engine swap on the C1
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Quote:

BeachBum wrote:
Quote:

jsup wrote:
I think we're having 2 different conversations. I don't disagree with any of that, my point pre dates it getting on the CNC.

My question is....was the part defective when it left the warehouse? That really in my mind is the only question.

There does not seem to be an argument that there were other parts that were defective when they left the warehouse.... is this one of those?


I think, that if the poster purchased the cylinder head as new from the manufacturer and it was certifiably identified with a problem such as core shift, that it should be replaced under warranty at no-cost.... that would be my opinion on that....


OK, we agree again, hey, look at that.

I would suspect that the date codes manufacturer's typically cast into the castings would identify if the said set were part of that run of known bad units. Should be easy enough to figure out. There is no denial of the problem, in fact quite the opposite, I read the above posted as an admission with a remedy to go buy their new stuff to fix it.

What I don't know is if the manufacturer ever replaced ANY of the units with this problem, maybe they did, maybe they didn't, but clearly they should have. If they never replaced any, then they have a point of saying "that's our policy". Shitty policy, but maybe it flies. If they replaced one, then I think they should replace them all. Would you want a product that "may or may not" be defective"?
Posted on: 2008/11/25 0:55
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jsup Re: Engine swap on the C1
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One last note. I was thinking about this. One head is damaged and one head isn't. So now we can blame the one damaged head on the machinist, what about the good head? Should that not be replaced?

The guy is still stuck with 1 unusable head. Ah....but the twist, to admit that one was defective from manufacture would be to admit both were.


Here's what I would expect the MFGr to do.

1. Offer new castings without springs and valves, re use the old ones, at a cost which covers his cost for the two castings. They'd look like a sport. The bare castings as a pair can't cost more than a few hundred bucks, $300 ish? So if AFR said, send me your old castings and for $300 we'll swap over the valves and springs, that would be almost fair and a happy compromise right?

2. If the old valves don't fit the new castings, replace the castings, he keeps the old valves, and buys new ones. Not the best solution, but a solution. He paid for a working set of heads and should get a working set of heads, but if its an upgrade to better heads, he'll pay for the new valves and sell his old ones. He could sell his other head(s) to cover the cost of valves...

There's a lot that I'm sure can be worked out, I don't see the solution of "just buy our new product" as an appropriate response. Service is what happens AFTER the sale, not before.

Let me just explain a little about how customer service should work. I buy Maui Jim Sunglasses. Know why? I slammed a pair under the hood of the vette and destroyed the lenses and the frame. I swept them up into a box, sent them back, for $60 I got a brand new pair in a week. These are $300 glasses, oh, and BTW, they are 10 years old.

That is customer service, I'll never buy another set of anything else again. On that note I have a set of Revos cost me over $250 if anyone wants them 1/2 price, they are brand new.
Posted on: 2008/11/25 14:29
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BeachBum Re: Engine swap on the C1
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Why was only one cylinder head damaged and not the other ? Were all ports damaged or only one ? What about the other ports done via cnc porting, were they okay ? Who determined there was core shift ?

Did somebody at AFR definitely determine the cylinder heads in question had core shift ?
Posted on: 2008/11/25 17:31
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