Whats the highest compression ratio you can go on LS1 and still run 93 pump gas. I'm not trying to get a complicated answer telling me about how you could go higher with a huge cam with alot of overlap and by messing with the timing. Just a basic guideline for a car with a mild cam and basic tune.

 

Cats or no cats (big factor here)? What altitude? 160 degree thermostat? Cooler plugs? Cold or hot climate? 12.5:1 air fuel ratio or more like 13.3:1? Timing advance?

I'm seriously not trying to get too technical but the answer to this question could be 10:1 or it could be 13:1.

 

The engine builders I have spoken to stick to around 11:1 when designing a street motor unless they have specific reason to do something else.

Some of us would be overjoyed to find 93. Im running 11:1 and I dont get better than Ethanol'ed 92 at the pump. (and Im not allowed to pump my own gas)

chris

 

Generally people stick with 11:1. Some go upto 11.3:1 but thats about it on a daily driven car with 93 octane.