Everyone I've talked to has said you can run up to a full point MORE compression on an EFI motor... over a carb.

Factory boys are running 12:1's and getting away with it...

Really just trying to educate myself more on the LSX builds. I know aluminum heads allow about a point more but my point was, is the knock sensor retarding timing to much if you push the limit? Why does EFI allow that much more compression?

Hopefully Steve jumps in here and tells us what the motorheads think...

But I've always been told that aluminum heads are good for about a point - and EFI is good for another one... and of course all of this is "STATIC" compression because the real number that nobody mentions is CYLINDER PRESSURE... and that is controlled (somewhat) by the cam...

Without hijacking Steve's thread, a 114 will build more cylinder pressure than a 112 or 110. I imagine it's ok due to a pretty radical camshaft for a LSX. Steve will fill us in...

Steve:

I was just reading of all the work you are doing to Penny. I really appreciate you running such a good and thorough thread for everyone I know it must take a ton of time. Penny is looking just great and I for one am learning a lot from your build.

I'll try and do the same for everyone when Lateral-1 starts it's new facelift.

Take care and keep up the good work.

Regards,

Ty O'Neal

Steve,
Did you say that the auto rad gave you extra clearance between the motor and the radiator itself? If so, how much space did you gain?

Precise fuel controll when tuned correctly.

I don't want to jack Steves thread -- but this whole "compression" and fuel management thing brings up some thoughts about the LSx motors....

I'm a pyro.... and as such understand a bit about "compressing" explosive chemicals...

I think that we all know "more" compression is a problem and that for the problems it creates - the power increase is actually minimal... Which got me thinking about why the factory LS motors use what we used to think was an unworkable compression ratio on todays pump gas...

But they seem to make great power - AND use LESS fuel to do it - and they're using leaner mixtures (except at WOT). So when you compress LESS fuel/air - you get a little more "bang" for your buck... So.... I'm thinking they're on to something here.... (and they employ built in safeguards). You take less fuel - atomize it really well - get more flow into the cylinder with better heads - then you compress the hell out of it... and you're making some power while sipping gas. The gas sipping is partly due to the leaner A/F they can run (coming back to the EFI issue)... The control with knock sensors... AND let's not forget the 6 speeds and tall gears... (low rpms per mile). BUT you have power when you want it because of great heads - and high compression ratios... then toss in some 12:5 AF at WOT....

Just thinking out loud here....

Aluminum heads run cooler than the
 

old steel heads. You can run a full point more on aluminum than you can steel.

Steve, you car is finally heading back in the right direction. Can't wait to hear how the new motor runs.

Are you bringing it back this way for RTTH?

I love ready this thread. Steve, it so neat to see how you keep improving on Penny.

Let me know next time you need a photo shoot Bitch, LOL. :thumbsup: