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L98 383 Stroker build 10 psi

6427 Views 20 Replies 7 Participants Last post by  S281
Hey so this is my first build and I'm trying to do it right the first time.
I'm building a 383 stroker for my 1986 Z28. Heres what I have

L98 block bored .030 over
Stroker assembly from enginekits.com
crank stroke 3.75
5.7 forged rods
12cc dished pistons
splayed main caps
novi 1000 with 10-11lbs pulley
1.6 crane gold rockers
hardened pushrods (stock length)

So with 64cc chambers the compression ratio should be 10.2:1 :yikes:

I know thats way too high to run 10psi so I want to know what size chambers should I be looking for 68cc, 72cc or..... size runners 190cc or 210cc?

Also what size cam? I want it to be a hydraulic roller cam.

I was thinking and airgap intake

btw it is a carbed motor. Unsure on carb setup aswell.

All help would be really appreciated. :beer:
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That is prefect compression for boost.
I've been told from just about everyone 9:1 or 8:0:1 is the better compression ratios to go with.


why is it you think 10.2:1 compression is good for 10lbs of boost????
Because it will make more power! That low compression shit is a myth hell my bikes are over 12.1 and they have no problem with boost.
Im at 9.8:1 on stock internals and have would have no problem with running 91 if i had a baller ass ignition system. You do need to watch out for detonation. If it does do that you will need to back the timing out like Conner said and use something like E85.

Question for Art though, what fuel do you use in your boosted bikes? Higher than 91, mix or something like methanol?
The first one was e85 this one is pump 91
Call comp tech line and give them your set-up: comp ratio, heads, weight of car, etc.. and they will give you your best options. Go with the bigger head option 210 cc and a 76 cc combustion chamber. If you lower the comp ratio you will have more room for higher boost numbers. Why did u go with a 5/7 rod when you could have gone with the 6 inch rod and had better rod stroke. Are you going to stay hyd roller on the l98?
Why run lower compression to just have to run more boost to make the same power? Boost=heat. Run lower boost with higher compression and make the same power as low compression and high boost. But have way better off boost driveabilty
And as far as the carb. Call up CSU tell them what you got and they will send you a carb ready to bolt on.
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