what a/f ratio do tuners shoot for, my car has a 355, lt4 h/c kit, shortys, loudmouth and some other little things. i dont think my tuner is doing it right cause on the dyno the a/f was 12.8/1 and he wanted it at 12.3/1. isnt that pretty rich?

 

considering stock is like 11.5:1, I'd say anywhere between 12.5-12.8 would be right. But if you make more power at 12.3:1, then you should run 12.3:1. You should base your a/f off of what makes the most power.

 

i thought stock a/f was around mid 14:1 and doesn't other tuners on here shoot for something like 14.7:1 for best performance

 

Part throotle AFR is 14.7, that is called "stoic".

Lean best torque is 13.0,,, best power is 12.6. So 12.8 sounds real good. I think that you want to run as close to 13.0 as you can get it without detonation. If you get KR, then run a bit richer and/or back off the timing.

If you are at 12.8 AFR (with a wide band O2 meter) without KR, then leave it alone, you are about perfect.