Has anyone tried putting an underpulley on their Z? Stillen is offering one. I know the ECU can fight some of the other power gaining mods like intake and exhaust, but I would think that an underpulley would be a pretty much guaranteed performance gain of a few horses and pounds per foot of torque. Just curious if anyone has done this, if they had noticeable gains, and if they've dyno'd the car before and after.

Thanks,
Craig