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MySCRocket1203
06-10-2005, 05:40 PM
i know our stock compression ratio is 8.2:1 and i know everyones trying to ad more boost but wouldnt it also work to raise the piston compression a little say up to 8.5 just below the stock n/a's i mean i know that would raise a new set of issues for timing and predets but it would be about the same as adding a few more lbs of boost different power band aside has anyone done this or has anyone made new piston heads for our cars if so who what where when and how much gains did they see over stock. (i was digging through my chilton guid notised we were 8.2 and the n/a 3.8 are 8.7 kinda struck me that maybe we could gain some by increasing our compression)

Jimmy 2Coupes
06-12-2005, 12:02 AM
94/5 SC's came with a 8.5:1 compression ratio from the factory if that helps. Also my SC's (94 and 95) would hit 15psi of boost on cool/cold days stock which they haven't been for some time now. Both now have 5% 0.D. pulley's and they both peg the boost gauge's real quick on WOT's. So far no problems but I do always run at least 93 octane in both.

MySCRocket1203
06-12-2005, 12:05 AM
94/5 SC's came with a 8.5:1 compression ratio from the factory if that helps.

my chilton guide shows 8.2:1 is the guide wrong its possible also if thats true would 95 pistons fit in my 1990 or are there better pistons to go with anyone try that yet let me know results

Tickler
06-12-2005, 03:25 AM
It's my opinion that it would be safer, cheaper and easier just to increase the motor's intake flow, or add more boost. If it were up to me, I'd lower the compression even more, and drop in some lightning parts. :cool:

MySCRocket1203
06-12-2005, 03:29 AM
I'd lower the compression even more, and drop in some lightning parts. :cool:

well im looking to follow in the footsteps of some of sccoas greats (building these engines) and im trying to learn what i can would it be better to go lower compression or more boost or would it be better to find a middle ground thats what im trying to discover