OPTIMUM Air/Fuel ratio....What's perfect for POWER!!!!

I have been noticing that as far as power is going, the fuel ratio of about 12.0-12.5 to 1 has worked for many as a great a/f ratio for dyno pulls. I know that for safety sake, I run mine at 11.5-1 as to make sure I don't run lean.

My question is based on the fact that from looking at the MOST POWERFUL list on the FAQ section, we have some great power being made in these numbers. I was just wondering what is optimum for power VS safety of the motor.

I assume that the leaner the mixture, the hotter the combustion gases and therefore more power. Maybe these people were running race fuel in their cars at the time of the run????

My only concern is for power numbers (not looking to make any championships....just trying to see for the future if running the timing as set and leaning out to 12.5-1 vs 11.5-1 would make a power jump or loss.

Guess it will be time to go to the dyno soon!!!!! (Not that soon, maybe in a few Months!!!!)


Don

Don,
I know that Dave D tunes to right about 11.9. That seems to be pretty close to the norm for safety issues. During my last dyno tune session, I saw well over 260 rwhp at around 4300 rpm but my af ratio was up to 13.5. Even though I was making good power at that level, it was just too lean for safety concerns, so it was backed down to 11.9 +/- .1 throughout the pull.

I trust Dave's tuning ability. I haven't gotten into the details yet in that regards, but I know that he knows what he's doing and that's good enough for me.