hey guyz

well i have 2007 chevy silverado

so what do u think of installing lsx block low C.R but the problem is i have a 225 EThead with 58 chamber it will raise my C.R to somewhere around 11 and thats alot for my turbo setup !!! so what do u think guys i want to go around 15 boost !! a garage told me u should order a pistons with 8 C.R so that u match between the block and the heads!!!!



so guyz what do u think !! i dont wanna get rid from my ETheads!!

 

Your post is a bit confusing from the language barrier, but I gather what you're saying. Just order a dished piston and you'll be able to get the compression to down around 9.5:1 or so even with those heads. You'll be fine then.

 

I agree. 9.5:1 is ok with 93 octane and 15psi boost. That is about the max you would be able to do without meth injection or a higher octane gas.

 

There are a bunch of dished pistons that will work. Even custom, keep the heads.

 

Over in the UAE they have like 95 octane for premium and it's fairly cheap from what I remember. Kinda jealous.

 

IIRC, UAE citizens also share in the oil revenue...REAL jealous!

 

nope its aint right we do pay as foriegners.



and we do have 98 octane so no worries about the fuel .

and sorry for my bad english guys but im doing my best .

ok now sorry what about 22 boost something like that would the 9:1 C.R will be good ??

 

With the 98 octane it might be ok. Anything above the 15 psi range gets risky on a LSx engine. Lifting the heads is the biggest worry. The thick deck of the ETP's will help with that but the high flowing head will cause your ideas with boost numbers to be skewed from a stock set of heads. Boost is a restriction in the intake manifold and intake runner across the valve. The less restriction you have the more air gets into the cyl. The more air in the cyl, the higher the cyl pressure regardless of manifold pressure.

What i'm saying is, don't get hung up on a boost number all the time. In order to get the same amount of air in the cyl with a stock head vs an ETP or such your boost levels will be different. For example: it may take 15 psi manifold pressure with a stock head to get the same amount of air as a ported or ETP head at 10psi. Turbo is pumping roughly the same amount of air.

 

thanks gibbs hmmmm then i think im gonna buy a new Et head or costum all PRO maybe the 245 with 70.03cc = 9.5 CR and get a dished pistons that will low it to 9 C.R . i want to reach 800rwhp something like that so i think ill have to get the iron block lq9 6.0 .