All you high boost + nitrous guys what are you running for internals? My goal is to have a 18* D1 Procharger ramming air down a 383. I heard 6.0" rods is a very bad choice, what length should I go with, 5.85 or 5.7? What crank, rods, and pistons do you use? What needs to be down to get 18+ psi from a D1?

 

Depends on the power level you want, but try and get the best you can for the budget you have. A 4340 forged scat crank, 4340 h beam rods and forged pistons should be fine. Who told you having 6" rods was a bad idea? I would stuff the longest rod you can in there to help on decreasing load on clyinder the cylinder walls. Not a huge deal but 6" rods are not any more expensive than 5.7" ones, so go for the longer ones.

Hunter

 

Combination Motorsports and a few others told me the same thing. The longer rods plus the dished piston was not a good idea.. which is why I went w/ 5.7 rods..

 

Strong pistons. Two brands I can vouch for are JE and Ross. I am using JE.

Forged 4340 crank from Callies, Lunati, SCAT. MIne;s from Callies.

A good 5.7" rod. The least I'd suggest are the Eagle H-beams. The next step up is the Lunati Pro-Mod or Manley's mid range rods. Some people feel you should go all the way to a billet rod like an Oliver or a Carillo. I am using a Lunati Pro-Mod and thye have held together, but I think the better rods would be a wiser choice.

Why 5.7"? Allows for thicker ring lands to provide more support to the piston rings, Moves the piston away from TDC more quicky than a longer rods, reducing peak cylinder pressure and the chance of detonation/damage.

Rich Krause

 

I have another question. When building a stroker wouldn't it defeat that if I used 5.7" rods? I thought 383s had 6.0" If you use shorter rods what would I have to do about pistons to compensate for the rods?

 

The longer stroke comes from the crankshaft, not the rod. The stock stroke in a 350 small block is 3.48", while a 383 stroker is 3.75", I believe the 396 is a 3.875" stoke. Running a standard 5.7" rod enables you to run a stronger piston. Running a 6.0" rod forces the wrist pin location closer to the piston top, and compromises have to be made with regards to piston design. Speed Pro (aka TRW) makes some very strong pistons, they would be able to take high boost. If you go with a scat crank, this will be cheaper because the forgings are made overseas, whereas callies and lunati are not. Scat has a good website, you should check it out.

 

I forgot that most people are using a stock deck block, if you can have a 9.325+ deck height, I would get the longest rods possible, especially in a boosted engine. They cost the same, and I have never see any negligable effect, but maybe someone else has. Please give me some experiecnes when long rods have done harm, I am curious to see.

Hunter

 

Are there bigger decks ltx blocks out there???

 

LQ4 CI block, Lunati 6.0 Pro billet SBC rods, JE forged alum 4.060 pistons, Lunati 4340 crank, teflon bearings, ARP 9/16" 8740 head studs, ARP 8740 main studs. 9.5:1 c/r, SCE .050 copper gaskets, receiver groove block, O-ring heads.

The 4.0 stroke requires some expensive machining of the crank throws to clear the piston skirts, but I have enough thickness in the piston for 1500 hp.

This is my current personal setup, versus what someone here has "heard" or "read" about other cars.

 

I think the thread is about a LT1/4 buildup though.

Rich Krause

 

sorry about that, maybe the moderator can delete it?

 

It may be about Gen 1 or Gen 2 blocks, but info about the Gen 3 can't hurt.