baldur

8.0:1 is fine, if your car is sluggish with 8:1 your engine management is in a bad state of tune.

Reddy

no matter how great the tune is; no compression + single cam + no boost = no ------- power down low.

baldur

no compression and the engine won't run at all, 8:1 is plenty of compression.

Reddy

omg, I didn't mean literally no compression. Look, you can argue all you want but what makes power...compression. Very low compression with no boost down low means no power. I've had experience with 10.1, 9.2.1 and right now I'm at 8.0.1 and all I'm saying is that I hate that low of compression and if I had a choice I wouldn't go lower than 9.5.1. And there's no way you can argue that lower compression will make more power becuase remember, boost is compression and compression makes power. This issue is widely debated and everybody has they're own opinion on it.

HMT-Admin

I agree with whitey, I've drove a few honda single cams with 8.5 c/r and one with 8.1, talk about complete dogs anything I build nowadays has a comp of around 9.5 minimum. My built ls/vtec is a 10.1c/r engine.

beerbongskickass

My stock Z6 is 9.2:1 compression and it's working out pretty well. I do plan on building my engine over the winter and will more than likely be going with 9:1 compression pistons. I was thinking about going with some endyn 9.6:1, but I figured since it's a daily driver and I will be running off pump gas most of the time I will make the turbo do all the work. I'm not really sure if there is a big difference between 9:1 and 9.6:1, but I'm guessing it will be tad bit safer.

jpcrx

coo thanks for all the advice. what numbers should i be running with built bottom w/ 20psi or should i go higher on the psi? with possible evo III 16g?