yup restrictive exhaust flow and incorrect carb jetting will make the car seem to run best with more than usual WOT timing. recycled residual Exhaust gas will not burn twice. over lean and over rich AFRs burn slower.
if it ain`t in the 34-36-38deg timing area at WOT something is off.
43 deg is too much at WOT on street premium unleaded pump gas
(some race only fuels have a slow burn speed for very high compression high rpm race engines)
If it makes x amount of ponies at 34-36deg and only makes x +2 horsepower at 38deg,,, use the lesser safer timing.
real world conditions on the street are never exactly the same all the time.
excessive spark advance costs money.
Last edited by F-BIRD'88; 03-28-2012 at 05:26 PM.