Re: supercharger pulley vs. crank pulley
There is a difference in the numerical ratios of the two competing belt turners. Id imagine the the inlet air temps of the two cars is coming into play and that your heating is pulling timing at the top end after you HEAT SOAK the intercooler.
Try rolling up to 80 or 90 and then punch it, youll probably get to 120 first before you pull back some. Just saying Woody