Quote Originally Posted by DR_EVIL View Post
If you look at the afr graph you can see why, between 6 and 7000rpm it was running leaner, the next run had more fuel and made less power.
Yeah but it could be that No1 Run was with cooler engine components (intercooler, intake, engine) So cooler charge, more oxygen, leaner AFR.
And atlower revs you lean out some, but you make less HP.
I dont think 0.3 AFR can make 6hp+ difference.