I wanted to know since most of you guys in here are boosting, what's the perfect air/fuel ratio? Or what do most of you guys shoot for to have the best combustion possible. I wanted to know, so it can give me something to shoot for also. How much is too rich, and how much is too lean. Thanks.

 

11-11.5 is good. anything under 11 is rich and anything above 12.5 is lean. Well 12.5 is already the leanest you want to be.

 

I would shoot for 11.8 under boost in a perfect world, and err on the rich side if your world is less than perfect. You are probably safe and would have nothing to worry about up to about 12.5 though.

 

Maximum power occurs at 12.5-13:1, but diminishes only slightly going down to 11.5:1. Power goes downhill fast at afr's lower than 11:1.

If detonation is not a problem, then tuning to 12.5:1 would yield the most power, but people like a little insurance against detonation and tune richer than that in order to run cooler combustion chamber temps. In some cases it would be better to retard timing a bit to suppress detonation and keep the afr higher.

 

Yeah im going to retard my timing to about 13 degrees, I heard it's better for boost. So I guess I will shoot for 12.5:1, with retarded timing to keep me on the safe side from detonation. Thanks.

 

a j&s would be a good investment for tuning for more power while keeping a hold on detonation and knock

 

I would suppose it depends on how accurate you can keep an a/f ratio. If you have just a fpr, then you have to really go on the rich side. But as your controls become more precise, the leaner you can go. ie.. if you have a standalone, you might be able to skirt the a/f leaner.