I would assume a larger port in the cylinder head and more volume in the intake manifold that peak tq rpm would have raised not not lowered by 20 rpm & your compression is up .5
This is interesting
Different day, different conditions. I don't put too much weight into the numbers.... especially 20 rpm. lol
Most of the pulls after the head work yielded higher rpm for the peak torque than before but not much higher. What I posted above was just where the highest numbers peaked.