Static Compression Ratio?

ECHO

New Member
#1
How much power are you guys making with off the shelf GN1 performance stock stroke 4340 rotating assembly? What are your ETs with boost numbers? I have JE pistons with 29cc dish well already which is like 8.5:1 CR. Will a 14 cc dish well volume with custom pistons be better at a 10:1 CR? My goals are to run in the 10's with 550+ horsepower 99% time on the street.
 

pacecarta

MAGNA
Staff member
#3
mid 9s on je .020 8.5CR pistons ,stock stroke forged external balanced , K1 rods , irons .051 cometics, 215/220 roller and TD 1.55 , ... HP around 820 93+alky drive it anywhere

with 10.1 youll need octane all the time so e85 or race fuel only .. no 93
 

BEATAV8

The Engine Whisperer
#4
@dvernst has had good results with his at ~9.7:1 using stock crank and rods. It runs much better than was ever expected, hitting 128-129mph with just 22psi boost from a 6266.
 

ECHO

New Member
#5
I’m converting to E85 120lb injectors, 450 fuel pump and Teflon lines. I will be upgrading to the TurboTweak ECM.
 
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earlbrown

runs with scissors
#6
With a 29cc dish (on stock castings) you'll never make any real compression. Even if you hit the head.


14 might be a little too small, and it'll most likely knock you out of any quench range.


When I make my pistons (22cc), I start at .040" off the head and see what I've got. 99% of the time that's when I stop. The only time I have to remove compression height is on the case of very small combustion chambers and stroker cranks.
 

Boost231

What's An Intercooler
Staff member
#7
What you have is more than enough for your goals. No need to spend money just to change pistons

Sent from my SM-G950U using Tapatalk
 

Mr.Spool

Well-Known Member
#9
How much power are you guys making with off the shelf GN1 performance stock stroke 4340 rotating assembly? What are your ETs with boost numbers? I have JE pistons with 29cc dish well already which is like 8.5:1 CR. Will a 14 cc dish well volume with custom pistons be better at a 10:1 CR? My goals are to run in the 10's with 550+ horsepower 99% time on the street.
with octane you can run more compression but what you need to understand is higher compression narrows the tuning window,lower compression widens it.more compression drives the turbo easier but with your goals anything would work.
 
#10
Yep as mr spool said you better be on your game if you start narrowing that tuning window because of higher compression you can get yourself in trouble