I've heard from a tuner that for a LS1 street car that by raising compression above 10.5:1 so much timing has to be removed that you lose hp. He is saying that being able to keep more timing will make more power than the higher compression setup would make with less timing.

Your thoughts please

 

I have 11.34-1 CR with my setup and had NO knock retard issues whatsoever. I'm not for sure but I believe my timing is around 28* and none was pulled cause of the higher compression. The rule of thumb is that for every full point you raise compression you'll gain ~4% throughout the powerband. I run 93 pump gas and have NEVER heard the car ping. Find a different tuner when you get your car done

 

Agreed!!!

Ive got 11:1 and run up to 28* on the top end and see no knock. Anyone who told you that running over 10.5 compression in an LSx motor isnt worth is should not be allowed anywhere near your car! Plenty of people running 11.5:1 on pump gas. Even 12.5:1 on some of the larger strokers still running knock-free on 93 octane. Granted having a bigger cam will help acheive this, but limiting yourself to 10.5 is selling yourself short.

 

There are many advantages to higher compression - more power, more torque, more efficient combustion, better fuel economy and provided you can get higher octane fuel and manage your cylinder temperature you can take full advantage of it including optimal timing.

If you have more valve overlap, higher compression also helps a good deal with your dynamic compression and therefor low end torque.