noboostnogo

so i have a perfectly fine bottom end laying around, its a 4 bolt 350 with flat tops, and 1 pc main. I just wanna build this little engine with some budget pparts. With my old 64cc my compression was about 9.2:1.

I am interested in bumping my compression up to about 10.5:1 so i can run the xr288hr. I wanna go with procomps because its a spare budget engine..

My question is what cc should i go with to bump my compression to 10.5:1??

I was thinking 60cc??

I will not cut them i will get them in that cc btw.

kenSS

iTrader: (1)

you are not going to get 10.5 with just the 60cc chamber. You need other pistons.

jg04222

i agree with kenSS; you're going to need some flat tops with two valve reliefs or approach it by playing with deck heights and head gaskets, but you have to watch you don't exceed the .040" minimum piston to head clearance; in other words if you zero deck it you're still going to have to run a minimum .040" head gasket.

The easiest way is to just use different pistons and have the bottom end rebalanced.

noboostnogo

i do have flat tops in there now

jg04222

do they have four valve reliefs or two?

ZONES89RS

iTrader: (25)

Well, with the same cam, i personally made great power with 9.7 to 1 compression. This was with a 383 on mid grade fuel. Those cams do not demand maximum compression.

noboostnogo

i still have some heads on the block but about 2 years ago when i put it together i think i remember seeing/buying the 4 valve relief. The block is a completely stock 350 stock bore and deck.



ZONES89RS what kinda power did you amke with that compression and the came?

brandoz28

iTrader: (3)

got a vortec headed combo 9.4:1 compression stock bottom end, with an xr288hr in it, edelbrock rpm non-airgap and some 1 5/8's shorty headers, and the horsepower comes out to around 430hp by the mph through the 1/8th. its kinda soggy under 3000 but after that it really comes alive. this is with a 350 in a 3600ish lb third gen camaro

noboostnogo

thats pretty good...

What cc should i go with to bump up the compression?? 58cc?

ZONES89RS

iTrader: (25)

Never dynoed it, but it was enough to destroy EVERY head and cam LS1 i ever run across, vettes, Zs and TAs