Lean = potentially better MPG
Lean = higher temps, potentially higher HP but this is not "safe" power

Hence why most "fuel economy" tunes don't allow towing much weight, if any at all.

Hence why tuning is both technical and yet an art and requires a brain, and not some curbsider selling trash.

Hency why WASHOOOOOOOOOBI'z require a tune to be safe and effective.

 

Hence why I run a stock air box with a drop in Wix air filter, yes the paper one.