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biggrizzly 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Chesapeake Beach, Maryland
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I'm considering just buying a built performance shortblock and selling my old block after the R&R if its worth anything at that time. The shortblock I'm considering has a fully blueprinted and race prepped block with ARP main studs, Mahle powerpack forged piston kit, Scat stroker I beam rods with 7/16 ARP capscrews, Scat 9000 series cast crank, and ACL bearings. However, it is not a four bolt corvette block. The builder uses standard 2 bolt LT1 blocks and installs splayed main caps which he told me are stronger than the 4 bolt caps. I have read this before, but wanted to get your opinion.

I'm also going to change my cam from the current grind that Brett Bauer specified for the 350 and put a different cam for the increased displacement of the 383.
Lloyd Elliot sent me an email this morning and said these two could be good choices with my LE2 heads.

A 218/224 .570/.565 111 LSA would work great in the 383 if you want something comparable to the way the cam you have works in a 350.

A 224/230 .573/.568 112 LSA cam would work great if you want something a hair more aggressive (but still VERY drivable)

What do you experienced engine Gurus think?
Posted on: 2010/9/27 22:26
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Don Haller
Corvette Club of America
94Coupe, 383Stroka, PeteK Trans, 3000stall, 3.54rear, Konis and bigger sways.
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PeteK Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Splayed caps installed properly on a 2 bolt block is much stronger that a stock 4 bolt main. Angling the bolts allow them to bite into a stronger part of the block.
If you are using a great block, decent rods, and quality pistons, it seems a shame to hang them on a cast crank. I would step the crank up to a better forged scat, or a Callies Compstar. The larger of the 2 cams is still quite mild. I would go with it.
Posted on: 2010/9/27 22:44
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Matatk Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Pete knows more than me, but I'd agree. I would go for the bigger cam, I wish I had a bigger cam in mine already.

Matthew
Posted on: 2010/9/27 23:49
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PeteK Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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I thought those cams were for a 350. A 383 with a great set of heads, and an lt1 type manifold will tolerate much more camshaft. The 2nd one is as small as I would go. If compression is going to be higher than 10.5 to 1, be sure to put enough cam to it to keep it from being a ping monster.
Posted on: 2010/9/27 23:56
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bogus Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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I agree, splayed is the way I am going when I do my engine.

I can't speak on the cam, tho... I do agree that a forged crank is well worth the extra $$.
Posted on: 2010/9/28 0:07
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biggrizzly Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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I'll have to find out the difference in price for the forged crank.
The cam can be modified at no extra cost. But I do have to pass Maryland emissions for a few more years.
Posted on: 2010/9/28 1:54
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Don Haller
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cuisinartvette Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Splayed keeps the caps from walking a little better
3rd cam
Dont know the requiremets you have on smog check into it..with a good tune I bet you pass.
Posted on: 2010/9/28 2:07
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rklessdriver Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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The biggest problem with the stock 4 bolt block is the caps. Specificially the fact they are made of regular old grey cast iron. It dosen't matter what kind of bolt/stud or anything you put on them... the cap itself is weak.

Aftermarket caps (good ones) are usually made of billet steel. The outer bolts being angled (splayed) put the threads in a stronger part of the block.

That said factory 4 bolt blocks are very strong. Plenty strong enough for the kind of HP most anyone can build N/A on pump gas.

Passing emissions throws a completely different wrench in selecting the cam. Personally I think cam 2 is as big as I would try and I think your tuner is going to have to be spot on.

Those that said to watch your compression ratio are correct. I know Mahle offers a 26cc dish, 16cc dish and flat top piston. You SCR would be very high (near 12.1) in a 383 with the flat top and 54cc LT1/4 heads. It would be crap with the 26cc dish. The 16cc dish would probally be the best.

Definatly get rid of the cast crank. I don't see why would spend $$$ to convert a stock block to splayed caps and then run a cast crank. Forged is the way to go. Should be about a $400-$500 upcharge for an import forged 4340 crank.

One last thing. KNOW who you are buying from. Just because they advertise on the internetz dosen't mean they are trust worthy. I've seen a few street engines from a "former NASCAR engine builder" shop in NC that were thrown together junk. A few guys that bracket race around here have bought engines from a place in "Henderson NV" that had "oil pan failure" at the first oportunity as well.
Will
Posted on: 2010/9/28 11:06
_________________
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.
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JAKEJR Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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KEMPNER, TEXAS
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Quote:

biggrizzly wrote:
I'll have to find out the difference in price for the forged crank.
The cam can be modified at no extra cost. But I do have to pass Maryland emissions for a few more years.


I don't understand what's meant by that (highlighted).

Definitely go forged. Even if your budget is a little lacking right now, hold off until you can buy a forged arm.

Of course I'm sure you know that the crank choice won't effect emissions. Whether the engine will pass or not isn't dependent on the crank being cast or forged.

Jake
Posted on: 2010/9/28 11:11
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biggrizzly Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Chesapeake Beach, Maryland
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Quote:

JAKEJR wrote:
Quote:

biggrizzly wrote:
I'll have to find out the difference in price for the forged crank.
The cam can be modified at no extra cost. But I do have to pass Maryland emissions for a few more years.


I don't understand what's meant by that (highlighted).

Definitely go forged. Even if yur budget is a little lacking right now, hold off until you can buy a forged arm.

Of course I'm sure you know that the crank choice won't effect emissions. Whether the engine will pass or not isn't dependent on the crank being cast or forged.

Jake


Uh Yeah! I know that! LOL

I was refering to the cam needs to be able to pass.
Posted on: 2010/9/28 13:53
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Don Haller
Corvette Club of America
94Coupe, 383Stroka, PeteK Trans, 3000stall, 3.54rear, Konis and bigger sways.
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vis_croceus Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Going by the cam size since that's all we have to indicate goals - stock 2 bolt block, stock caps, and cast crank will be more than sufficient.
Posted on: 2010/9/28 15:16
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biggrizzly Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Quote:

vis_croceus wrote:
Going by the cam size since that's all we have to indicate goals - stock 2 bolt block, stock caps, and cast crank will be more than sufficient.


This is the same LE2 heads and cam motor I modifed a couple years ago with a top end rebuild with heads done by LE and the cam specified by his partner in crime Brett Bauer. Goals are the same, 350-400 RWHP, mostly cruising around town, occasional autocross, occasional drag racing, but nothing outragous. I already have all the supporting mods (40lb injectors,hogged out intake, LT headers, bigger TB, MSD Opti etc.) I just want the bottom end redone after spinning a rod bearing this past spring. I really think a good cast crank will be adequate as well. Hell the stock engine did awesome for 150,000 miles! The SCAT cast crank is supposedly better than a factory crank.
Posted on: 2010/9/28 15:45
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Don Haller
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pr0zac Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Quote:

JAKEJR wrote:
Quote:

biggrizzly wrote:
I'll have to find out the difference in price for the forged crank.
The cam can be modified at no extra cost. But I do have to pass Maryland emissions for a few more years.


I don't understand what's meant by that (highlighted).

Definitely go forged. Even if yur budget is a little lacking right now, hold off until you can buy a forged arm.

Of course I'm sure you know that the crank choice won't effect emissions. Whether the engine will pass or not isn't dependent on the crank being cast or forged.

Jake


I think you may be the only one that didn't understand what he was going for.
Posted on: 2010/9/29 13:31
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Matatk Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Don asked me briefly about my crank, I have a scat cast crank in my 383 build. I didn't think the forged was necessary for a street motor under 500 hp without spray or a power adder. My builder agreed. He said a forged motor on a street car like mine is so you can sell it down the road or tell all your friends you have a forged rotating assembly. Here's a quick article:

http://www.popularhotrodding.com/tech ... rankshaft_tech/index.html

Matthew
Posted on: 2010/9/29 17:18
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biggrizzly Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Thanks Matt, Interesting article.
Has anyone here done business with Clayton Racing Engines?
I have talked with Corey at Clayton a few times and him and his dad build the shortblock I have been discussing. He essentially gave me the same information that Matt and Pete have given me, but he recomends a forged crank for anything over 500hp and says that these LT1 383 engines can reach 500hp pretty quickly. He also said I should remind myself that he talks flywheel hp and not RWHP. With all this said I still think for my aplication the Scat cast crank will be more than adequate. I really can't see this thing pulling down that kind of HP. I didn't dyno it before the failure, but it was probably somewhere between 350 and 375 I guess, so at a minimum I'll maybe get another 30hp for the increased cubes and if I get a good tune maybe a bit more. So perhaps 400 at the wheels and around 475 at the crank. That would put me still in the safe zone and it could only be used to take momma to the ice cream store and not much drag racing!!!
Posted on: 2010/9/29 18:39
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Don Haller
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94Coupe, 383Stroka, PeteK Trans, 3000stall, 3.54rear, Konis and bigger sways.
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383tpimachine Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Corpus Christi
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I follow the better safe than sorry method.
Posted on: 2010/9/29 19:05
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rklessdriver Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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I don't know them personally - but the Claytons have a pretty good reputation within the industry. Seems pretty sharp from the post I've seen over on a well known engine building/performance industry message board.

IMO neither of those cams with your heads will make enough HP or turn enough RPM to require you have a 4340 forged crank... but I'd still recomend one. Espc considering the $$$ spent to convert that F Body block to billet 4 bolt caps. Running a cast crank at that point seems like a parts mis-match.

Now rebuild your stock Y Body 4 bolt block or convert one via a set of straight bolt cast iron caps and a cast crank makes sense.
Will
Posted on: 2010/9/29 20:17
_________________
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.
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biggrizzly Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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A new option has risen today. I was put in touch with a local shop that has a significant background in F-Body LT1 engine builds. I talked to this shop a couple years ago about setting up my Ring&Pinion swap, but didn't give them much thought until today when I went into a local Speed Shop (Speed Unlimited) near where I work. I ran into the same guy that ran the shop two years ago and he told me to give him a call later. I just got off the phone and he is going to work up some prices for a couple different options. He also favors the forged internals. So... the saga continues
Posted on: 2010/9/29 22:32
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Don Haller
Corvette Club of America
94Coupe, 383Stroka, PeteK Trans, 3000stall, 3.54rear, Konis and bigger sways.
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iCorvette Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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I have the same crank in my 383, and past CA smog with the Comp 280 xfi one step bigger
Posted on: 2010/9/30 0:26
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JAKEJR Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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The word "modified" should give you a clue.

Jake

Quote:

pr0zac wrote:
Quote:

JAKEJR wrote:
Quote:

biggrizzly wrote:
I'll have to find out the difference in price for the forged crank.
The cam can be modified at no extra cost. But I do have to pass Maryland emissions for a few more years.


I don't understand what's meant by that (highlighted).

Definitely go forged. Even if yur budget is a little lacking right now, hold off until you can buy a forged arm.

Of course I'm sure you know that the crank choice won't effect emissions. Whether the engine will pass or not isn't dependent on the crank being cast or forged.

Jake


I think you may be the only one that didn't understand what he was going for.
Posted on: 2010/10/2 13:55
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biggrizzly Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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I think the misunderstanding was my fault.

I meant "modified" cam specs. Not to modify the actual cam.
That's why its important to say exactly what we mean on these forums. Sorry for any confusion.

Cheers!

Quote:

JAKEJR wrote:
The word "modified" should give you a clue.

Jake

Quote:

pr0zac wrote:
Quote:

JAKEJR wrote:
Quote:

biggrizzly wrote:
I'll have to find out the difference in price for the forged crank.
The cam can be modified at no extra cost. But I do have to pass Maryland emissions for a few more years.


I don't understand what's meant by that (highlighted).

Definitely go forged. Even if yur budget is a little lacking right now, hold off until you can buy a forged arm.

Of course I'm sure you know that the crank choice won't effect emissions. Whether the engine will pass or not isn't dependent on the crank being cast or forged.

Jake


I think you may be the only one that didn't understand what he was going for.
Posted on: 2010/10/2 14:14
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Don Haller
Corvette Club of America
94Coupe, 383Stroka, PeteK Trans, 3000stall, 3.54rear, Konis and bigger sways.
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JAKEJR Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Not a problem; I'm with you on accuracy and precision
and I try to keep down as many as I can in my posts. But, hey, none of us is perfect so it happens.

My primary concern is not to critique anyone's grammar, etc. but when I respond I want to be as sure as I can that I actually understand what the OP means.

I'm a member on about ten other Forums and I do the best I can in the reading comprehension department. Most times I can figure out what the OP or responder "meant" but occasionally I can't; that's when I ask for a clarification.

I just updated my profile so that other members can see I'm actually NOT an idiot, LOL.

No harm; no foul.

Thanks for understanding.

Jake

Quote:

biggrizzly wrote:
I think the misunderstanding was my fault.

I meant "modified" cam specs. Not to modify the actual cam.
That's why its important to say exactly what we mean on these forums. Sorry for any confusion.

Cheers!

Quote:

JAKEJR wrote:
The word "modified" should give you a clue.

Jake

Quote:

pr0zac wrote:
Quote:

JAKEJR wrote:
Quote:

biggrizzly wrote:
I'll have to find out the difference in price for the forged crank.
The cam can be modified at no extra cost. But I do have to pass Maryland emissions for a few more years.


I don't understand what's meant by that (highlighted).

Definitely go forged. Even if your budget is a little lacking right now, hold off until you can buy a forged arm.

Of course I'm sure you know that the crank choice won't effect emissions. Whether the engine will pass or not isn't dependent on the crank being cast or forged.

Jake


I think you may be the only one that didn't understand what he was going for.
Posted on: 2010/10/2 14:53
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JAKEJR Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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BTW, I'm in the process of going through much the same things as you are so I figured I share what I'm doing. I'm in the parts selection process to build my son a 415 LT1 for his 96 Vette.

Since it's HIS car, I've been trying to get a good handle on how he wants the engine to perform - off idle torque, idle quality, exhaust note (you know how young guys are about that - 23), etc. We don't have tail-pipe in my County, just ALDL connection for SES codes. So I've got a bit of a break there.

I've got Engine Analyzer Pro's simulation program which is supposed to be one of the best on the market for data input, etc. I've been plotting in various cam profiles to see what the differences there are in their various characteristics. I'm pulling them out of CompCam's latest catalog right now.

I changed his heads (Dart Pro 1s; 180 cc, actually 189.8 when measured by me), cam and rockers last summer on his stock bottom end 350 and now we're going up in CID. I had a custom CompCams grind made for the 350, so I'm using it's characteristics as a base line for a new cam. That is, to see if a new cam is what's called for.

What I've done is plug in all the specs on his 350, as it is now, and ran a simulation then saved it for graphing. I then created the new 415 engine on the program but with the same HR that's in his 350 now. Then I did a comparison of the two.

From that point I plugged in the specs of many different CompCams offerings so as see what difference, if any, they'd make when installed in the new 415.

I then used EAP's auto chain function to have the program automatically play with the duration specs in 4 degree increments. I'm also playing with LSA differences; then rocker ratio differences, etc., etc. What I'm primarily interested in are the DIFFERENCES between them - not the accuracy of the numbers, themselves. See what I mean?

If I run different cam specs that show an average of, say, 20 lb/ft torque and/or HP increase from the cam he's now running, then I'll know I'm moving in the "right" direction. That is unless the DCR goes too high or something like that. Lots of variables to juggle, LOL.

After all the research I did last year, I decided on a single pattern profile and he's been happy with it, but going up 65 inches may make a significant enough difference to call for another profile - and, yea, another $300, LOL

I just began the EAP Chain function yesterday and, right now, I'm in the same range as you are for a cam- the 218/224 - 224/230 - 230/236 @ .050 area. Since his car is a DD, there are a lot of variables to be considered, a lot other things just merely looking at torque and HP.

I installed a set of Dart Pro 1s on his 350 last year and used the flow numbers from a few different sites (not just Dart's) to get a representative idea of their flow range (not much difference from Dart's #s I might add.) Anyway, I used EAP's percentage CFM flow feature to increase head flow CFM in 5% increments to see if there'd be justification to have his stock 180 cc Darts ported to achieve a 5% flow increase. I'm looking at the cost/benefit side of the picture on that.

In other words, I'm trying to see if it would be of a cost benefit to have them ported for the power increase that it would provide. So far it seems doing that wouldn't be worth the cost. I'm still in the analysis part though, so I haven't made a decision on that.

May well turn out to be the same as with the cam.

Hope some of this helps.

Jake
Posted on: 2010/10/2 15:34
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96 Vette; 388 CID, all forged bottom end, ported AFRs, etc.
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SpectatorRacing Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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1721 Posts
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For your motor it makes no difference whether you go 4 bolt or 2 bolt with splayed caps. Go with the cheaper option and don't take the upsell if it's offered. I've been running my original 1993 LT1 4 bolt 383ci with 400+ RWHP at 6700 RPM for 5 years now. Hot Rod builds 2 bolt F body's with 400 HP all the time. I've never heard of one giving out. Doesn't mean it doesn't happen, but I woudn't worry about it if it were my money.

I'd go forged on the crank, though. No question. I got a lightweight (8 lbs less than stock) Eagle forged number for less than a grand. I can look up the part number if you want to know.

In fact, I have another equal crank in a box in the garage with the balancer bolt stuck in the nose. If anyone knows how to get it out I could let the thing go for near nothing...I just want get it out of my garage
Posted on: 2010/10/2 16:48
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Steve40th Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Quote:

JAKEJR wrote:
BTW, I'm in the process of going through much the same things as you are so I figured I share what I'm doing. I'm in the parts selection process to build my son a 415 LT1 for his 96 Vette.

Since it's HIS car, I've been trying to get a good handle on how he wants the engine to perform - off idle torque, idle quality, exhaust note (you know how young guys are about that - 23), etc. We don't have tail-pipe in my County, just ALDL connection for SES codes. So I've got a bit of a break there.

I've got Engine Analyzer Pro's simulation program which is supposed to be one of the best on the market for data input, etc. I've been plotting in various cam profiles to see what the differences there are in their various characteristics. I'm pulling them out of CompCam's latest catalog right now.

I changed his heads (Dart Pro 1s; 180 cc, actually 189.8 when measured by me), cam and rockers last summer on his stock bottom end 350 and now we're going up in CID. I had a custom CompCams grind made for the 350, so I'm using it's characteristics as a base line for a new cam. That is, to see if a new cam is what's called for.

What I've done is plug in all the specs on his 350, as it is now, and ran a simulation then saved it for graphing. I then created the new 415 engine on the program but with the same HR that's in his 350 now. Then I did a comparison of the two.

From that point I plugged in the specs of many different CompCams offerings so as see what difference, if any, they'd make when installed in the new 415.

I then used EAP's auto chain function to have the program automatically play with the duration specs in 4 degree increments. I'm also playing with LSA differences; then rocker ratio differences, etc., etc. What I'm primarily interested in are the DIFFERENCES between them - not the accuracy of the numbers, themselves. See what I mean?

If I run different cam specs that show an average of, say, 20 lb/ft torque and/or HP increase from the cam he's now running, then I'll know I'm moving in the "right" direction. That is unless the DCR goes too high or something like that. Lots of variables to juggle, LOL.

After all the research I did last year, I decided on a single pattern profile and he's been happy with it, but going up 65 inches may make a significant enough difference to call for another profile - and, yea, another $300, LOL

I just began the EAP Chain function yesterday and, right now, I'm in the same range as you are for a cam- the 218/224 - 224/230 - 230/236 @ .050 area. Since his car is a DD, there are a lot of variables to be considered, a lot other things just merely looking at torque and HP.

I installed a set of Dart Pro 1s on his 350 last year and used the flow numbers from a few different sites (not just Dart's) to get a representative idea of their flow range (not much difference from Dart's #s I might add.) Anyway, I used EAP's percentage CFM flow feature to increase head flow CFM in 5% increments to see if there'd be justification to have his stock 180 cc Darts ported to achieve a 5% flow increase. I'm looking at the cost/benefit side of the picture on that.

In other words, I'm trying to see if it would be of a cost benefit to have them ported for the power increase that it would provide. So far it seems doing that wouldn't be worth the cost. I'm still in the analysis part though, so I haven't made a decision on that.

May well turn out to be the same as with the cam.

Hope some of this helps.

Jake

I want a 415, whats the block, stroke etc etc on this. LT1's are so limited.
Posted on: 2010/10/12 5:46
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JAKEJR Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Quote:

Steve40th wrote:
[quote]
I want a 415, whats the block, stroke etc etc on this. LT1's are so limited.


+.060" (4.060") bore and 4" stroke. LT1 block with Oliver main caps in all five positions.

Bore X Bore X Stroke X .7854 X 8 is the formula for calculating CID.

You have to clearance the block by grinding on it vas needed for crankshaft clearance and choose a crank that'll clear the cam, too. Lunati makes one.

Jake
Posted on: 2010/10/13 13:23
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My son, Ryan M. Cameron, graduated from West Point on 22 May 2010! He was commissioned as a 2nd Lieutenant and I pinned on his first pair of "Butter Bars" PROUDEST DAY OF MY LIFE!!
96 Vette; 388 CID, all forged bottom end, ported AFRs, etc.
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Steve40th Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Quote:

JAKEJR wrote:
Quote:

Steve40th wrote:
[quote]
I want a 415, whats the block, stroke etc etc on this. LT1's are so limited.


+.060" (4.060") bore and 4" stroke. LT1 block with Oliver main caps in all five positions.

Bore X Bore X Stroke X .7854 X 8 is the formula for calculating CID.

You have to clearance the block by grinding on it vas needed for crankshaft clearance and choose a crank that'll clear the cam, too. Lunati makes one.

Jake

Thanks jake, I knew the formula, but I thought the 4 inch stroke was very questionable on our blocks.
Cant wait to see this.
I think there was one guy, SONNY VA, who had a 415, correct o CF.
Posted on: 2010/10/13 13:40
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JAKEJR Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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It's basically a clearancing issue; a little grinding here and a little there, LOL. Breaking through at the oil pan rails is always a concern.

I found a crank designed to clear a .900" base circle cam with .660" valve lift out of the box, so seems that part of it has been addressed.

I was SURE I saved the link but when I went looking for it the other day, I couldn't find it in my Bookmark section. IIRC it was a Lunati.

Jake
Posted on: 2010/10/16 23:25
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My son, Ryan M. Cameron, graduated from West Point on 22 May 2010! He was commissioned as a 2nd Lieutenant and I pinned on his first pair of "Butter Bars" PROUDEST DAY OF MY LIFE!!
96 Vette; 388 CID, all forged bottom end, ported AFRs, etc.
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BrianCunningham Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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My indexed splayed caps

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Posted on: 2010/10/17 19:11
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NCCC Governor: http://BayStateCorvetteClub.com
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JAKEJR Re: 4 Bolt Main Corvette Block versus Splayed Caps 2bolt LTx
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Using my new engine specs, with Engine Analyzer Pro V.3.9 simulator, the XFI 218/224 cam showed the broadest, highest torque band when compared to the 224/230.

The 224/230 isn't listed in my catalog as a XFI grind but one of the mags had one custom ground for use in an engine build up they were doing. In Comp's catalog, the XFI grinds jump from 218/224 to 230/236 with NO 224/230 shown.

I had to choose the 224/230 specs from the XE grinds, not the XFI. So that "could" make the difference.

224/230 would be the logical cam between the 218/224 and the 230/236 since many of Comp's cams move in 6 degree increments.

I just ordered Comp's Camshaft Master Catalog, so maybe the XFI 224/230 lobes will be in it. If they are I'll re-run the simulation and post the results.

But for now and for the engine I'm building for my son's 96 LT1 Vette, the 218/224 makes the most and best power. Could be this is an example of bigger not being better, but I'll know for sure once I plug in the XFI 224/230 specs (assuming I can find them).

BTW, his car is a DD and the engine's being built for best torque NOT HP.

Jake
Posted on: 2010/10/24 20:36
_________________
My son, Ryan M. Cameron, graduated from West Point on 22 May 2010! He was commissioned as a 2nd Lieutenant and I pinned on his first pair of "Butter Bars" PROUDEST DAY OF MY LIFE!!
96 Vette; 388 CID, all forged bottom end, ported AFRs, etc.
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