|
|
Register To Post |
| rklessdriver | New LTX running well but..... | ||
|
Senior Guru
 
|
I'm still having freaking valve train problems. The car was making good power then just took a crap at 5800RPM. I have a boat load of dyno sheets and it's making 440RWHP at 5800RPM then taking a nose dive. Over 400RWTQ from 3800RPM until 5800RPM (DEAD FLAT TQ CURVE) where it suddenly just takes a dive....
[IMG]http://i50.photobucket.com/albums/f303/rklessdriver/Corvette/BillyWillams92Vette.jpg[/IMG] Aparantly everybody who swore to me that Morel lifters would take 400lbs of valve spring over the nose (no problem) was full of crap. I pulled a valve cover (again) and my .620 lift cam is measuring just shy of .530 @the valve when its warmed up, I'm sure its doing wonders for the effective duration as well. When its cold I'm getting the full .620, but anythime the oil temp goes over 200F the lifters bleed down. I've had this motor on an engine dyno quite a few times figuring out a valve float problem early on and my current springs solved that problem, I can't for the life of me figure out why the lifters are bleeding down, NOW that I've got it in the car. Maybe they got damaged from all the previous dyno time and finally failed. SO Sweet!! I get to change valve springs (again), except this time motors in the car not on a dyno stand. PSI and my cam grinder are working with me and I've got a spring on the way that's 135lbs @1.800(seat) and 360lbs@1.150 (over the nose). Should solve the lifter bleed down problem but if not, I guess I'll be pulling the Intake, Rev Kit and replacing the Lifters. At least the car runs and drives kinda. I got the car back from Ed (The HP Factory) a few weeks ago and he has it tuned really well for WOT, but since I've still got single wire O2's, it won't go closed loop.... The driveability is pretty much crap with an open loop tune. He has a bunch of timing taken out at low throttle openings and the car goes from occasionally trying to die or spitting back and no power (under 1/4 throttle) to explosive wheel spin (anything over 1/4 throttle). Its like an on/off switch. Then to add insult to injury it just runs out of steam right when it should be pulling the hardest, althou you can't tell anything in the lower 3 gears because of the tune situation it just lights the tires up for no reason and anything approaching WOT results in an instant trip to the Rev Limiter. However if you get it hooked up in 3rd gear and slowly roll into the throttle you can feel it pin you in the seat right up to about 6000RPM where it slowly tapers off to the rev limiter at 7200RPM. I really wish I had better results to post for myself (well at least Nolands engine turned out like I expected right). With a carb my engine dyno'd 608HP@6800RPM, and pulled cleanly well past 7400RPM once everything was sorted. If the freaking thing would keep pulling/climbing at the same rate it is pulling/climbing now on the chassis dyno, it would be right around 490-500RWHP@6800RPM. I will keep everyone posted on what happens. I've got a few other little things I have to fix first (massive rocker cover leak, changing the dash cluster and wiring the car for heated O2's) that are pissing me off (even more than the valve springs/lifters) before I tackle chainging the springs/lifters. Will |
||
Posted on: 2008/10/22 18:39
|
|||
|
_________________
1984 Corvette. 434 SBC with a Powerglide. Best pass - 8.48@160MPH 1.23 60ft on MT 275/60R15 Radials. 1972 Corvette. LS5 454 BBC with M20 4 speed. Best Pass - Doing good to just pass a gas station. |
|||
 Transfer
|
 
|
||
| bogus | Re: New LTX running well but..... | ||
|
Grand Imperial Pooh-Bah
 
|
Have you looked into the Hydra-rev kit?
I wonder if hydraulics can deal with that much nose pressure? |
||
Posted on: 2008/10/22 18:46
|
|||
|
_________________
The single biggest problem with communication is the illusion that it has taken place. - George Bernard Shaw Education is the best tool to overcome irrational fear. - me |
|||
|
Transfer
|
|
||
| rklessdriver | Re: New LTX running well but..... | ||
|
Senior Guru
|
Quote:
Yes. It currently has one one it. That's why I'm going for changing the valve springs first. Seems easier than pulling the intake and Rev Kit and lifters. The bad thing is I shouldn't have to change anything. The motor ran fine on the dyno right before I put it in the car. Plenty of other engine builders are running way more spring pressure on these Morel lifters (I only have 150lbs/400lbs). Of course the oil got diluted bad with fuel from idling it around on 36lb injectors with the stock tune, but I changed it before I dropped the car off with ED to get tuned. Maybe the lifters got damaged from that. I'm hoping the lighter spring pressure will bring them back, but if not I'll be replacing the lifters next... Will |
||
Posted on: 2008/10/22 19:10
|
|||
|
_________________
1984 Corvette. 434 SBC with a Powerglide. Best pass - 8.48@160MPH 1.23 60ft on MT 275/60R15 Radials. 1972 Corvette. LS5 454 BBC with M20 4 speed. Best Pass - Doing good to just pass a gas station. |
|||
|
Transfer
|
|
||
| BrianCunningham | Re: New LTX running well but..... | ||
|
Senior Guru
 
|
Why the single plane intake over a ported stocker or Edelbrock?
|
||
Posted on: 2008/10/22 19:24
|
|||
|
_________________
Polo Green 95 LT1 6-spd http://mysite.verizon.net/vzevcp74/ 383 LT1/Vortech Supercharger/AFR heads/Rod end suspension/Penske-Hardbar dual rate coilovers/Wilwood 6pot brakes NCCC Governor: http://BayStateCorvetteClub.com |
|||
|
Transfer
|
|
||
| rklessdriver | Re: New LTX running well but..... | ||
|
Senior Guru
|
The air distribution is better and the runners are longer in the single plane.
Will |
||
Posted on: 2008/10/22 20:10
|
|||
|
_________________
1984 Corvette. 434 SBC with a Powerglide. Best pass - 8.48@160MPH 1.23 60ft on MT 275/60R15 Radials. 1972 Corvette. LS5 454 BBC with M20 4 speed. Best Pass - Doing good to just pass a gas station. |
|||
|
Transfer
|
|
||
| BrianCunningham | Re: New LTX running well but..... | ||
|
Senior Guru
|
Is it possible the elbow is choking it at high rpm?
You could check that with a temporary plate so the throttle body it directly over the intake facing down. Kinda like a 2 barrel carb if you follow me.  Here's AKS Racing's for comparision: [QUOTE]AKS Racing: I will say that the cast fuel rail mounting bosses are a great idea. The general concept is great, however, the water / t-stat housing will have to be completely re-engineered. You should have heard the bs story I got when I bought the intake used mounted by 10/28 x 2 1/4" screws that were used to hold the rails in position (not to mention that the rails were not set to the proper height for injectors). Mix that set-up with 60 psi fuel psi on full boost, and you have rails that lift and a massive fuel leak. I am just fortunate that the fuel did not make it to the glowing header. It nearly cost me my car. :mad: Some CF members will "say anything" to make a sale. A lot of work (read as lots of welding to lower / level the rails, fill the original holes in the wrong location, beef up new bolt hole area, locate and drill and tap correct 1/4 x 20 mounts, re-weld complete TB plate area, as it was thin and porous and had been ground very thin in areas (looked to be leaking), reweld parts of the water passages, then re-machining all of these areas, etc) went into fixing the "hack job" that I was sold. And to top all of this off, on occasion this member still tries to sell more units made like the one he sold me. :nono: Purchase a quality product from a reputable vendor, and make sure you know what you are getting. Here is my finished product, off the car, then installed. [IMG]http://i55.photobucket.com/albums/g151/AKS_Racing/100_0118.jpg[/IMG] [IMG]http://i55.photobucket.com/albums/g151/AKS_Racing/100_0928.jpg[/IMG] Aaron[/QUOTE] |
||
Posted on: 2008/10/22 20:46
|
|||
|
_________________
Polo Green 95 LT1 6-spd http://mysite.verizon.net/vzevcp74/ 383 LT1/Vortech Supercharger/AFR heads/Rod end suspension/Penske-Hardbar dual rate coilovers/Wilwood 6pot brakes NCCC Governor: http://BayStateCorvetteClub.com |
|||
|
Transfer
|
|
||
| cuisinartvette | Re: New LTX running well but..... | ||
|
Elite Guru
 
|
Went through a similar predicamnet with a 347 recently..HR in the 242/248 .600 range. 150-180 lbs would have eventually caused a failure, chanced 135 and all worked out well. Honestly this is where Id draw the line and use a solid you eliminiate the weaknesess of a hydraulic at that point. 7400 on a HR you are brave.
|
||
Posted on: 2008/10/22 21:04
|
|||
|
_________________
You will be redirected to that thread. Click here if your browser does not automatically redirect you. |
|||
|
Transfer
|
|
||
| rklessdriver | Re: New LTX running well but..... | ||
|
Senior Guru
|
Quote:
I've thought about the elbow and 58mm TB hurting it at higher RPM but honestly I don't think it is. Quite a few others are running 10.0's with this same set up on a 430inch Gen 1 motors. Maybe its the angle of the pic that makes it look less tall than his. Mine is 3 3/8 tall at it's shortest point. Will |
||
Posted on: 2008/10/22 21:49
|
|||
|
_________________
1984 Corvette. 434 SBC with a Powerglide. Best pass - 8.48@160MPH 1.23 60ft on MT 275/60R15 Radials. 1972 Corvette. LS5 454 BBC with M20 4 speed. Best Pass - Doing good to just pass a gas station. |
|||
|
Transfer
|
|
||
| rklessdriver | Re: New LTX running well but..... | ||
|
Senior Guru
|
Quote:
I totally agree... Normally. However after months of research (before I ever bought anything) and taking with other engine builders, I got convinced that these Morel's would stand a buch more spring pressure. Heck Chris Straube runs 200lbs/500lbs on his off shore BBC's using Morel's and dosen't have any problems. He is convinced the lifters are faulty. I am tempted to: 1. Put a mech roller in it. But If I do I'll be buying time on my crank and rods. The lobes I'm looking at are real nice and mild, but it will still put me 30-50HP stronger than it should be now. It is all untra light stuff and not really desgined for over 600HP. 2. Put a mild hyd roller in it similar to the Reed I speced for Nolands car. Then put a LT4 intake on it, turn it 6500RPM and call it a day. Instead of flying off the handle and changing everything one way or the other here, I'm going to try the new PSI springs first, then if that fails to solve the problem change the lifters. I spent a lot of development time and money here with what I have and I'd like see it run to tis potential. Will |
||
Posted on: 2008/10/22 22:11
|
|||
|
_________________
1984 Corvette. 434 SBC with a Powerglide. Best pass - 8.48@160MPH 1.23 60ft on MT 275/60R15 Radials. 1972 Corvette. LS5 454 BBC with M20 4 speed. Best Pass - Doing good to just pass a gas station. |
|||
|
Transfer
|
|
||
| cuisinartvette | Re: New LTX running well but..... | ||
|
Elite Guru
|
The lifters are going to bleed down some once you shut if off, guessing with a lot of spring even moreso. Wondering if a bit more preload wouldnt help.
Anywho, its just opinion (sure you already know this) HR lifters just dont seem to like being over 6500 on a regular basis. Heavier +pump up issues, etc at a point calls to make the next step. Heres a HR that was pushed too far. [IMG]http://i118.photobucket.com/albums/o103/gfsmith/DSC00433.jpg[/IMG] Not being critical btw just of the opinion a HR isnt going to live at 7k let alone 7500 for very long. Keep us posted on your diagnosis. |
||
Posted on: 2008/10/24 2:12
|
|||
|
_________________
You will be redirected to that thread. Click here if your browser does not automatically redirect you. |
|||
|
Transfer
|
|
||
| Deakins | Re: New LTX running well but..... | ||
|
Guru Newb
 
|
Well the above was probably caused by valve float; when we do that with solid rollers we just beat the bearing out of em and drive the wheel further and further into the body of the lifter (I haven't had one disintegrate in there yet but some guys have brought them back pretty close)... Reckless, what weight of oil are you running in the engine? Also, I'm with Brian on this one, you really need to determine if this problem is related to the induction. It is suspect that the engine did not lay down on the engine dyno with a carburetor, but does now with the efi mod. All the points you brought up are valid and may be the cause; it just seems prudent to start with the only real change made from then to now.
|
||
Posted on: 2008/10/24 15:42
|
|||
|
Transfer
|
|
||
| rklessdriver | Re: New LTX running well but..... | ||
|
Senior Guru
|
Dekins-
I'm running 15W40 Rotella T HD. My main/rod clearance is a bit tight (.0028/.0022) to be running 20W50. I may try some just for GP thou... The only way to tell about the induction is to re dyno it with one of those 4bbl TB's if I can borrow one from some one. I guess I could also put a vacume gauge on the plenmum and see how many inches it pulls at WOT... Crusin- I know they bleed down with no oil pressure but I've tried to minimize that as much as possible. I could fill the page here with how many times I've run it with the the rocker cover just laying on the head and then measuring the lift as soon as I sut the car off. Like i said if the oil is cold, little to no bleed down. Oil over 200F, massive bleed down. I do plan to put the pre load at 1/2 a turn (currently 1/4 turn) when I switch the rocker covers out... as soon as I can get the drivers side welded back together. Thought about bottoming it out with a .020 feeler guage (like a Rhodes lifter) also. Thanks for the replys. I've still got a few trouble shooting measures to try out before I actually take anything apart. Like I said the car still runs well. It's just not where it should be. I will keep you guys abreast of what happens. Will |
||
Posted on: 2008/10/24 22:13
|
|||
|
_________________
1984 Corvette. 434 SBC with a Powerglide. Best pass - 8.48@160MPH 1.23 60ft on MT 275/60R15 Radials. 1972 Corvette. LS5 454 BBC with M20 4 speed. Best Pass - Doing good to just pass a gas station. |
|||
|
Transfer
|
|
||
| BrianCunningham | Re: New LTX running well but..... | ||
|
Senior Guru
|
Quote:
You could try mounting the stock one pointed up so it looks like a 2 barrel. Kinda like this  All you need is an adapter plate |
||
Posted on: 2008/10/25 0:59
|
|||
|
_________________
Polo Green 95 LT1 6-spd http://mysite.verizon.net/vzevcp74/ 383 LT1/Vortech Supercharger/AFR heads/Rod end suspension/Penske-Hardbar dual rate coilovers/Wilwood 6pot brakes NCCC Governor: http://BayStateCorvetteClub.com |
|||
|
Transfer
|
|
||
| cuisinartvette | Re: New LTX running well but..... | ||
|
Elite Guru
|
Another thought comes to mind, at higher rpm its my opinion that 400 lbs spring pressure isnt enough to go 7500. Wondering if you arent having a valve control issue.
Did you have a hole in the tuning so to speak when it was at Eds or did it get sorted out? Curious to see the final outcome on all this. Edit: Keep an intake with a plenum if you can. Acccording to Joe Sherman the intake with a plenum will always make more power than the straight shot of the single TB setup. Just regurgitated info but Id trust what he says.He talks about it a fair amount on speedtalk (trying to find the thread but am out of town-limited comp. time) |
||
Posted on: 2008/10/26 14:40
|
|||
|
_________________
You will be redirected to that thread. Click here if your browser does not automatically redirect you. |
|||
|
Transfer
|
|
||
| pr0zac | Re: New LTX running well but..... | ||
|
Elite Guru
|
tell me your name really isn't william williams??
|
||
Posted on: 2008/10/26 15:45
|
|||
|
_________________
96 lt4. 357ci, 11:1, LE 226/232, LE2 LT4 heads, ported LT4 intake, EM Gladiator44, EM LT's, stock exhaust, NX kit. |
|||
|
Transfer
|
|
||
| Re: New LTX running well but..... | |||
| Guest_ |
What cam are you using in this build?
|
||
Posted on: 2008/10/26 20:44
|
|||
|
Transfer
|
|
||
| rklessdriver | Re: New LTX running well but..... | ||
|
Senior Guru
|
Crusin-
He turned it 7000rpm on the chassis dyno. It never floated the vlaves and it pulls cleanly above 6000rpm it just quits making power above that. No holes in the tuning as the rev limiter is set to 7200rpm. With the rev kit it went 7400 on the engine dyno before I shut it down. It was out of power by 7200 (HP peaked at 6800) but it didn't float the valves at 7400, so I called it a day. I was as surprised as heck when Ed called me and told me it was making great power (440RWHP)but it wouldn't pull past 6000rpm. Since I had so may problems with valve springs making RPM on these lobes (very aggressive with an inverse flank)when I first put the motor together, I pretty much knew this was some more of the same. We wasted 3 dyno sessions during development time getting it to make the power I wanted. I thought I had it solved on the last one but I guess not. At this point I'd be happy with it just making power to 6800RPM. Should be easy to do that but with theses cam lobes I got maybe not.... There's so many possibilities as to what could be wrong. When I first got the motor in the car, it was super rich on the stock tune. I didn't run it much more than idle it for some pics, and on and off the trailer to Eds. Even thou I changed the oil before I took it to Ed (and it was full of fuel)the new oil looks pretty bad after the chassis dyno session must have been a lot more gas left in there. The internal valving in the lifters could have been damaged by the gas in the oil. The internal valving in the lifters could have been damaged by all the valve float problems I had in the development period and they finally gave up. I got a bunch of spring on it and a combination of factors above collasped the lifters and they are not comming back. Like I said I got a few things to do before I take it back apart. I should have my valve covers fixed by next week and then I'm going to try some fluching the oil system and running some different oils. If none of that gains the power back up over 6000RPM, then I'm going to change the springs. If that don't fix it I'm going to change the lifters. If that sson't fix it... I'm going to have to make a descision. Mech roller or milder hyd roller. Pr0zac- No it's Billy Williams. But like everything in the Marine Corps things get butchered and for the past 12yrs my name has been "Will". Even thou I've been out a year and a half I still answer to it. TPI-guy- The cam is a custom grind from Mike Jones (Jones Cam Designs). 288/292@.006 242/246@.050 .620/.620 (1/7/1.7) 106IC/110LS. other engine specs 382 cubic inches 10.6 SCR 43lb pendlum undercut 4340 crank (3.75 stroke) 545gr Scat Q lite 4340 H beam Rods (6.0") 398gr 2618 Weisco pistons (4.030)w/99gr tool steel pins AFR 210 Elims CNC comp port T&D Shaft Mount rocker system Morel lifters Hydra Rev Converted Victor 2925 58TB w/36lb injectors Will |
||
Posted on: 2008/10/27 1:54
|
|||
|
_________________
1984 Corvette. 434 SBC with a Powerglide. Best pass - 8.48@160MPH 1.23 60ft on MT 275/60R15 Radials. 1972 Corvette. LS5 454 BBC with M20 4 speed. Best Pass - Doing good to just pass a gas station. |
|||
|
Transfer
|
|
||
| jsup | Re: New LTX running well but..... | ||
|
Elite Guru
|
Here's my thoughts, and please don't shoot the messenger.
1. the intake, I think those injectors are too small. If I read correctly you dynoed with the carb then went to injection, that's where the problem started. 2. The tune, how do you know it's right, not saying it isn't, just how do you know it is? 3. The valve train. To spin 7400 you need titanium valves, retainers, locks, etc...those components don't hold up 4. The rocker shaft looks like a T&D shaft, long chunk of aluminum. Take a look at Jesel Pro Series if you want to be serious, that rocker shaft looks consumer grade, hardly good enough. 5. The rev kit may help a bit with lifter weight, but it's not going to do anything with 7400 RPMs. Some will tell you rev kits are great, others will tell you they are junk. Depends on who you talk to. Always consider the source when getting that info. 6. Finally, to compare to a big block with the same tension springs and lifters is not a fair comparison, they are bigger lifters. My .02 and that's about what it's worth. bottom line is that HR lifters are only good to 6500 that's it. |
||
Posted on: 2008/10/27 17:41
|
|||
|
_________________
Parts don't make power, engines make power. |
|||
|
Transfer
|
|
||
| rklessdriver | Re: New LTX running well but..... | ||
|
Senior Guru
|
Jsup-
1. Yes it was dyno'd with a carb because our dyno is not set up for EFI. However I have had nothing but problems with these cam lobes. When everything is right it makes big power but I had to run 3 different sets (and working on a 4th) of valve springs and retainers to get this far. I've had nothing but problems getting the RPM and HP I wanted out of it. These problems have been with me from day one, way before the EFI switch. 2. Considering the A/F ratio is pretty much dead flat on 12.5:1, too boot even with mech problems its making more power than 90% of the normally aspriated LTX's out there... I'm guessing ED did a decent job on the tune. 3. I know what it takes to turn that kind of RPM. People did it 30yrs ago with flat tappet solid lifter cams and 1.250 valve springs. FYI since I'm trying to do it with a real hyd roller cam, something not many other engine builders have ever been able to do without shimming up lifters plunger travel, I've got the right parts. 4. Wayne Jessel makes a good prouduct but I had a choice when I went and spent nearly $1300.00 on rockers. I bought T&D for a reason and its got nothing to do with how it looks. 5. The rev kit does help. Most people who knock them have never even run one before. Since we have always used them in our oval track motors and never had any serious lifter problems, I KNOW their value. 6. Actually all GM engines (BBC/SBC even the LSX) use the same .842 dia lifter. I'm also using the same rocker ratio as a BBC (1.7)so the comparison is closer than you know. It's a brave new world out there for hyd rollers and RPM, and I intend to prove it. I've already had it run as intended on our dyno. These problems are most likely a collasped set of hyd lifters from: 1. Contaminated oil 2. Previous abuse 3. Running the valve spring pressure on the ragged edge. or a failed set of lifters from a combination of 1,2 and 3. DOn't worry I'll get it sorted. It's not something I can do in a day thou with the other nit picking crap I have to take care of first and regular work everyday. Will |
||
Posted on: 2008/10/28 21:37
|
|||
|
_________________
1984 Corvette. 434 SBC with a Powerglide. Best pass - 8.48@160MPH 1.23 60ft on MT 275/60R15 Radials. 1972 Corvette. LS5 454 BBC with M20 4 speed. Best Pass - Doing good to just pass a gas station. |
|||
|
Transfer
|
|
||
| jsup | Re: New LTX running well but..... | ||
|
Elite Guru
|
Quote:
Cool, thanks. I appreciate the response....keep us posted we can learn something... I was just spewing some random thoughts that I thought could help. |
||
Posted on: 2008/10/28 21:41
|
|||
|
_________________
Parts don't make power, engines make power. |
|||
|
Transfer
|
|
||
| Steve40th | Re: New LTX running well but..... | ||
|
Elite Guru
 
|
Ona side note for the dirty oil etc. Mine, my 396 LT1 from More Performance, had dirty oil within a few miles of running it. I used AMSOIL, Mobil1, Rotella and all the same, with AMSOIL and WIX filters. COme to find out, the pressure was over 60 psi till warm, which caused the oil to bypass the filter (GM's answer to oiling regardless). I believe factory bypass valves are 50-60psi? The white Z28 spring many use is 70 psi. Well mine was around 80psi till 180-200 degrees.
So, I changed the spring (lowered my mellings pump down to about 50 psi cold, Hawaii cold 80 degrees) and I blocked the bypass. I have now gone 400 miles and oil, Shell Rotella Diesel still clean. I also changed rings to standard tension. I am not sure how much this affected the dirty oil, but my clearances were .018 on rings. w/SRP pistons. Also, on lifters, I was told HR factory GM is fine till 6500. This was LPE and several others. Granted your lift is pretty high, but it is a reputable company, LPE. |
||
Posted on: 2008/10/29 0:30
|
|||
|
_________________
Ko'u ohana aia ku'a ikaika |
|||
|
Transfer
|
|
||
| Deakins | Re: New LTX running well but..... | ||
|
Guru Newb
|
As a fellow engine builder with 10 years of experience working with everything from Top Alcohol drag engines to 410 Sprint Car engines I have to say Jsup is right on.
First, if you feel the need to run that many RPM you will have to buck up and buy some titanium parts (although since you dont have enough cylinder head to make great power up there I dont know why you are insisting upon turning it that high). You simply will not be able get the seat pressure you need when using a hydraulic lifter. Secondly, the T&D shaft system you bought is far from the hot ticket for an application like this. The system Jsup mentioned is extensively machined to reduce the weight that the valve sees while being comprised of more durable parts (its lighter and can take more abuse). Theres a reason that when we (and even the Nextel Cup guys) have a choice, we run Jesel See that's the real point and you are missing it badly; with the flawed configuration that you chose, you have to control your valve action with compromised spring pressures. If you want to come in and play with the big boys you gotta pay at some point. I don't care if it can take a few dyno runs and not have problems; how many miles before it starts shooting parts out of the tail pipe? Have you ever heard the phrase "you have to finish the race to win it"? In this case, how many miles do you want it to go? 100, 1,000, 10,000? Lastly, most big block engines that come through turning very many RPM have been upgraded to a larger lifter (heck, most of the small blocks are going that way as well). There are a few reasons we do this but the simple fact is the stock size has been an issue for a lot of years, so when we are allowed to get away from it we do as fast as possible! It kinda boils down to the above saying; you cant push the limit like you are wanting to with stock type parts, and cheap ones at that. We deal with these types of issues in the racing world all the time; I would have thought such an experienced, crack engine builder would have already known and anticipated these facts before building a time bomb. But then again, as a professional, I dont go around asking people what I can and cant get away with |
||
Posted on: 2008/10/29 15:13
|
|||
|
Transfer
|
|
||
| CSS996 | Re: New LTX running well but..... | ||
|
Mega Guru
 
|
Let's keep this friendly.
|
||
Posted on: 2008/10/29 21:38
|
|||
|
_________________
Currently "Between Vettes". 
|
|||
|
Transfer
|
|
||
| VETTHRET | Re: New LTX running well but..... | ||
|
Guru Newb
|
Quote:
:psycho: Quote:
He had enough cylinder head to make 600HP, which was his goal so in fact you are wrong again, he DID have enough cylinder head. Those who have enough cylinder head to make 600HP, have it written on their dyno sheet, those who don;t have it written only in their sig  Quote:
Yeah going over 7000RPM is unheard of with the T&D rockers. Better phone up the guys using T&D in NASCAR and let them know that. Quote:
He's trying to push the limits of a hydraulic roller, did you not read that part? [/quote] Quote:
Neither did he, he was just updating us with whats going on. I suppose as a professional, you've seen it all and know it all? You can predict the outcome of any combo? Diagnoss any problem? Nothing has ever surprised you or not gone as planned on the first shot? That's nice you can build a combo that works over and over again but if everyone just did that we would all still be running carbs on the street. Will is trying to do something new, break new ground and that is rarly ever accomplished on the first try. He's experimenting, cut him some slack. If the guys at NASA can blow up a Space Shuttle, don't think you're perfect. |
||
Posted on: 2008/10/29 23:37
|
|||
|
Transfer
|
|
||
| rklessdriver | Re: New LTX running well but..... | ||
|
Senior Guru
|
Dekins-
I'm not about to get into a pissing contest with you over nothing. I apprecieate the criticism. So keep on trying to knock me down a peg and talking shit about the parts I used and how everything else on the market is so much better. However I NEVER asked anyone here for their opinion on what I could and couldn't get away with. I DID pass along some info about the problem I'm having and the proposed solutions of a few trusted engine builders, my cam grinder (Mike Jones) and Jerry over at PSI valve springs. Some folks (you included) wanted to give their .02 and IMO thats fine... I'll even entertain YOU, since I know you and your boy here were just looking for an opening to shoot your mouth off. Will |
||
Posted on: 2008/10/29 23:41
|
|||
|
_________________
1984 Corvette. 434 SBC with a Powerglide. Best pass - 8.48@160MPH 1.23 60ft on MT 275/60R15 Radials. 1972 Corvette. LS5 454 BBC with M20 4 speed. Best Pass - Doing good to just pass a gas station. |
|||
|
Transfer
|
|
||
| VETTHRET | Re: New LTX running well but..... | ||
|
Guru Newb
|
Quote:
Exactly. You do know why he picked on you right? I'l give you a hint...it starts with A and ends with R. Honestly, if you pick on a guy and his cylinder head/parts choice who just made over 600HP on his LT1 with a streetable hydraulic cam, truly you have an agenda. |
||
Posted on: 2008/10/30 0:04
|
|||
|
Transfer
|
|
||
| pr0zac | Re: New LTX running well but..... | ||
|
Elite Guru
|
my dad can beat up your dad!
|
||
Posted on: 2008/10/30 0:48
|
|||
|
_________________
96 lt4. 357ci, 11:1, LE 226/232, LE2 LT4 heads, ported LT4 intake, EM Gladiator44, EM LT's, stock exhaust, NX kit. |
|||
|
Transfer
|
|
||
| cuisinartvette | Re: New LTX running well but..... | ||
|
Elite Guru
|
rkless has enough head to achieve his goals and then some, just a matter of sorting out valve control issues. If he wants to experiment let him. If he pulls it off, good for him if it breaks Im sure he will fix it and seems to have the capacit to.
Dont tell anyone but some people actually post up what they are doing rather than just talking about it with no pic, proof, nothing. |
||
Posted on: 2008/10/30 3:47
|
|||
|
_________________
You will be redirected to that thread. Click here if your browser does not automatically redirect you. |
|||
|
Transfer
|
|
||
| Schrade | Re: New LTX running well but..... | ||
|
Elite Guru
|
Ah yes!!! Instant replay!
Quote:
|
||
Posted on: 2008/10/30 3:59
|
|||
|
_________________
LT5, Marc Haibeck ECM module, AUTOMATIC!!! 
|
|||
|
Transfer
|
|
||
| BrianCunningham | Re: New LTX running well but..... | ||
|
Senior Guru
|
When did this turn into CF?
|
||
Posted on: 2008/10/30 4:21
|
|||
|
_________________
Polo Green 95 LT1 6-spd http://mysite.verizon.net/vzevcp74/ 383 LT1/Vortech Supercharger/AFR heads/Rod end suspension/Penske-Hardbar dual rate coilovers/Wilwood 6pot brakes NCCC Governor: http://BayStateCorvetteClub.com |
|||
|
Transfer
|
|
||
| CSS996 | Re: New LTX running well but..... | ||
|
Mega Guru
|
Technical threads need to be informative.
A couple of you are abusing the forums. It needs to stop now. You'll just need to agree to disagree, and leave it at that, or you'll self-destuct. Hopefully everyone can get past this, and help the forum grow. |
||
Posted on: 2008/10/30 20:00
|
|||
|
_________________
Currently "Between Vettes".
|
|||
|
Transfer
|
|
||
| jsup | Re: New LTX running well but..... | ||
|
Elite Guru
|
Quote:
Serious...guess I can't post there people feel the need to come here to beat me up for no reason. I'm being stalked on the internet!!!!    |
||
Posted on: 2008/10/30 20:53
|
|||
|
_________________
Parts don't make power, engines make power. |
|||
|
Transfer
|
|
||
| Deakins | Re: New LTX running well but..... | ||
|
Guru Newb
|
Alright lets be technical about this. First, I apologize if I came off a little rough in the last post; I deal with similar situations everyday and they are a little annoying (I take work home with me). Lets look at this from what you want, have, and what you want/need to accomplish it.
Now, the goal here is to run the engine at 7500RPM with the hydraulic roller cam. So here are the problems that I see. First, when we normally look at running this amount of RPM we look to a mechanical tappet. The main reason for this is simple; the amount of seat pressure required to control the average valve train is too high for the hydraulic tappet to survive for any period of time. Generally they just squish down and create all sorts of fun symptoms. This leads us to the problem at hand; how do we control the valve action with light enough spring pressures to ensure the survival of the hydraulic tappet while maintaining at least some factor of safety? The answer is you dont; you can not get around the physics involved in the process of operating the average valve train at the required rate without the pressure! Now, valve control issues are not new and not limited to hydraulic tappets. We have problems with mechanical tappets and the absurd amount of load we want to run on them (every engine can not operate in its environment with a 400lbs at the seat set up). If you look at the vast majority of race engines that are utilizing a lot of lift and a lot of RPM (that have to survive for more than 7 seconds) you will see that they have done one major thing. They have reduced the mass of the valve train and thus, reduced the amount of spring pressure; this includes everything from the valve itself to the retainer, lock, rocker arm, pushrod and the tappet itself. They also go to great lengths to ensure that the rocker arm assembly is lubricated to the extreme (bathing the valve spring in oil to keep its temp down). They do this because you can not bend the laws of physics; either you have the mass and the spring pressure to control it or you dont have the mass, in which case you dont need the spring pressure to control it. So in this case the cure is as simple as replacing some of the heavy parts with lighter ones; or changing the goal of the project. The first place to look when shedding mass is the valve, then move to the retainer, then the lock, then the rocker arms, and lastly the pushrods. Since you are running the hydraulic tappet and have the rev kit you will not be able to shave the mass that we do on the different applications but thats ok. So again, my apologies if I offended you; I was not calling your T&D shaft junk, it simply is too massive for the job (it would be at home with 700lbs open pressure). If you drop the spring pressure will you be able to rely on this engine at 7400? If you lower the operating range is the camshaft the one you want in there? If you have the funds and dont mind the work you may (and I say may because 7400RPM is a tall order for any hydraulic tappet) be able to lower the mass down enough to use the package as you designed. Unfortunately parts that are made out of titanium are expensive, and sometimes hard to get but if high RPM out of a hydraulic is what you want, from where I sit thats the only option. Just my .02 |
||
Posted on: 2008/10/30 22:48
|
|||
|
Transfer
|
|
||
| jsup | Re: New LTX running well but..... | ||
|
Elite Guru
|
Here's the problem with Deakins....
He's an aeronautical engineer by trade who builds all kinds of flavors of race engines. Street, Drag, sprint, circle track..he worked on fighter jet designs. He builds race, street, track engines daily to pay his bills, he's a professional motor builder by trade who participated in an apprentice program when younger with a well respected builder, before he went on to get his degree in engineering. Many times he is constrained in the operational environment which the engines need to operate. So he has to do what he needs to do in the parameters he is allowed to do things. This takes a lot more thinking than what most of us here do. And that kind of thinking can really change how you think about motors and builds. The result of his experience and education is that he tends to write dry posts than no one ever reads, so he trys to take the controversial route, so at least people read it, and the point gets lost in the controversy. I suggest that Deakins start writing technical, and I hope people pay attention. On paper, he is the most qualified guy here. Now, I'm not saying what he says is gospel, but dammit people, just on his resume' alone listen to the guy. How often are you going to find a guy with his qualifications doling out free advice. He's built 100s of engines with over a decade of experience in all different disciplines. Just because he may see the world differently than some catalog builder, does not make him wrong. Everyone gets their underwear in a knot as if they have been personally attacked if he mentions that something can be done better one way over another....I don't get that. So if we can all be civil and pay attention to the information WE ALL CAN CONTRIBUTE and stop this petty attachment to a perceived way of doing things perhaps we can all learn something. Otherwise threads will continue to go down the shitter. No one knows everything despite what you all may think of yourselves. Deakins has offered what I consider valuable information when I was going through this, and I questioned every comment and double and triple checked what he told me, and frankly what everyone else has told me. So did cuisenartvette, and I fact checked him and even PeteK on the trans (no offense pete) got fact checked. So if you can get your ego out of the way you just may learn something. The difference is when I told im I thought he was full of crap, he didn't resort to personal attacks, he took the time to explain WHY he says what he says. He didn't ask for dyno numbers or timeslips, or tell me about a guy he knew, get all pissed off, and call me names. I think a few can learn from that.... I took the opposing side of every position he took until he demonstrated to my satisfaction he was right. Something many people won't do. So Deakins, stick to the technical, this isn't CF people here will read and appreciate it, regardless how dry. It won't help to get attention to the facts here with insults. Just sayin'.. I am saying this as I believe he can be a valuable technical resource for everyone, as he has proven to be for me. |
||
Posted on: 2008/10/30 23:07
|
|||
|
_________________
Parts don't make power, engines make power. |
|||
|
Transfer
|
|
||
| Matatk | Re: New LTX running well but..... | ||
|
Webmaster
 
|
Quote:
 You know too much. Ban him. Matthew |
||
Posted on: 2008/10/31 0:28
|
|||
|
_________________
2002 EBM convertible, Magnusson supercharger, cam, headers, etc. 1989 Corvette...RIP |
|||
|
Transfer
|
|
||
| rklessdriver | Re: New LTX running well but..... | ||
|
Senior Guru
|
OK
Well I finally got my new rocker covers all cut up and welded back together. Most important thing I needed to do was stop the oil leak from catching my car on fire everytime I tried to drive it farther than around the block... I made good use of my CDO day (love that Govt job) and kinda documented what needs to happen if you ever want to run these 18 degree style Moroso rocker covers on an LTX Corvette. First your going to need the specs to start cutting. Now mine had to clear the rocker stand on the inside which over hung the stud boss by about .250 and that made it real tight trying to clear the lower bout of the Alt body but these measurements got it done. The angle cut on the top half of the rocker cover is to clear the Alt brg support. [IMG]http://i50.photobucket.com/albums/f303/rklessdriver/Corvette/CorvetteValvecover.jpg[/IMG] Now your going to have to start cutting on those $350.00 works of art Moroso sells. I used a cut off wheel and a die grinder. [IMG]http://i50.photobucket.com/albums/f303/rklessdriver/Corvette/Clif.jpg[/IMG] Start bending some sheet alum to patch up the hole and weld it all back together. You can see I tried to re use the part I cut off but in the end I had to just fabricate an entire new piece. [IMG]http://i50.photobucket.com/albums/f303/rklessdriver/Corvette/Clif1.jpg[/IMG] Installing them on the car. Because they are so much taller than the stock rocker covers and my previous Carbonfiber ones, I ran in to some interference with the Alt/AC compressor bracket. I had to grind the accessory bracket (quite a bit) to clear. [IMG]http://i50.photobucket.com/albums/f303/rklessdriver/Corvette/DSC00942.jpg[/IMG] Installation complete. [IMG]http://i50.photobucket.com/albums/f303/rklessdriver/Corvette/DSC00939.jpg[/IMG] [IMG]http://i50.photobucket.com/albums/f303/rklessdriver/Corvette/DSC00941.jpg[/IMG] One last thing. Before with the Carbonfiber rocker covers, I had to space the alt up about 1" to clear them. This presented a real problem the first time I got on the car on the street. The motor moved over and the Alt quickly chewed a nice little hole in my hood. These cut up Morosos allowed me to place the Alt back all the way down in the stock bracket and I didn't have to grind on the Alt body for clearance anywhere. As you can see plenty of clearance everywhere. [IMG]http://i50.photobucket.com/albums/f303/rklessdriver/Corvette/DSC00940.jpg[/IMG] While I had the rocker covers off I also re-adjusted the lifter pre load. I went from .020 (anout 1/4 turn) to .050 (3/4 turn). Morel seems to think this will quiet them down and put the plunger in a better position to retain the oil in the lifters plunger cavity and prevent them from bleeding down. More pre load is against everything I know about running hyd lifters but if that's what Morel says to do, I'm all for it. I have run the car to check for leaks (Thank GOD there are none) and the lifters are a bit quieter... Tomorrow... I need to drain and flush the fuel filled oil out. Also since my Alt is now back in the stock location I need to find a 68" belt (the stock 67" won't ever think about going on and the 69.5" I have is way too long) to put on it. Once that is accomplished I'll take it out from some test runs (on a closed course, naturally). Hopefully it will have a nice lean miss above 6000rpm. Will |
||
Posted on: 2008/11/7 21:59
|
|||
|
_________________
1984 Corvette. 434 SBC with a Powerglide. Best pass - 8.48@160MPH 1.23 60ft on MT 275/60R15 Radials. 1972 Corvette. LS5 454 BBC with M20 4 speed. Best Pass - Doing good to just pass a gas station. |
|||
|
Transfer
|
|
||
You can view topic.
You cannot start a new topic.
You cannot reply to posts.
You cannot edit your posts.
You cannot delete your posts.
You cannot add new polls.
You cannot vote in polls.
You cannot attach files to posts.
You cannot post without approval.
|
|