So is KFZWOP the maximum brake torque from a spark point or maximum spark before knock?
Obviously higher octane fuel even if you manged to push past this point doesn't mean you making maximum torque, but then again a slower burning fuel would require more advance to meet the optimum torque.
So just cause you get past a point in KFZWOP in KFZW without knock doesn't mean it's actually the opimum torque so I guess some dyno work is required to measure actual torque outputs here?
Lower compression pistons would be an obvious one as the front of the piston sits lower in cylinder so the combustion chamer is larger and therefore at the same burn speed it will take longer for the burn to reach the piston.
IIRC Rick said that by going to E85 it is possible to exceed KFZWOP table in KFZWOP. That way it will act as limiter and optimal ignition isn't correct anyway for e85. DYNO TIME