Compression ratio on a Procharger car
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Compression ratio on a Procharger car
What kind of compression ratio is everyone running on their Procharged cars? I've seen a lot of people around 9.5:1 and lower and obviously people are doing it on stock ls1's and ls2's which are almost 11:1. But I was looking to run around 15psi on a forged 347 or wherever my D1SC will max out at and found a affordable piston/rod combo that would put me at 9.775:1 with the heads I already have (patriot lq9's) which are 72cc's. Am I playing with fire or would I be okay? Should I wait for something better to keep the ratio down? I was thinking about finding the thickest head gasket I could find to offset it a little bit or run some race gas but I'd like to drive it quite abit in the summer. So let's hear some numbers and some set ups? Maybe mileage to if you have it.
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I ran 10# on the stock comp. with nothing more than a small blower grind and valve springs and made 570Rwhp. I didnt like the 100+ degree days too mutch with the stock 3.5" dual coolers. It went to the track once and did 11.35 @130 on the everyday 18" Kumhos and full weight.
#4
Originally Posted by JASON11WS6
What kind of compression ratio is everyone running on their Procharged cars? I've seen a lot of people around 9.5:1 and lower and obviously people are doing it on stock ls1's and ls2's which are almost 11:1. But I was looking to run around 15psi on a forged 347 or wherever my D1SC will max out at and found a affordable piston/rod combo that would put me at 9.775:1 with the heads I already have (patriot lq9's) which are 72cc's. Am I playing with fire or would I be okay? Should I wait for something better to keep the ratio down? I was thinking about finding the thickest head gasket I could find to offset it a little bit or run some race gas but I'd like to drive it quite abit in the summer. So let's hear some numbers and some set ups? Maybe mileage to if you have it.
9.75:1 will be just fine with 93 octane fuel. Add a methanol kit and you don't have to retard the timing as much. We recently picked up 35 rwhp by adding a methanol kit and adding timing back into the engine. Bob
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Originally Posted by Exotic Performance Plus
9.75:1 will be just fine with 93 octane fuel. Add a methanol kit and you don't have to retard the timing as much. We recently picked up 35 rwhp by adding a methanol kit and adding timing back into the engine. Bob
#6
Originally Posted by JASON11WS6
Even with 15+ pounds of boost? No problems on 93? Is their any advantage to running a mix of water/meth or is it better to go straight meth?