That was a typo meant to say AFR. Correct me if i'm wrong but doesn't the stock engine have an AFR of about 14.9:1 from 1,300 to 3,000 rpm at low-end, 13.1:1 from 3,200 to 6,200 rpm in the midrange and richens up at the top end (12.0:1 and lower) from 6,300 to redline? If these numbers are leaner by 0.5 is that really going to be detrimental to the engine?