T25/T28s are lagy, lagy all the way around. I dyno'ed 340hp with out Test pipes and IC's, and i was runing 15psi on 91 octain and stock timing. Went to the track with Test pipes Ic and 100 octain and pulled a 12.8 with a 2.0 60ft. So its hard for me to decide between Manifolds and my t25/t28s or ported manifolds with sport 500s.