I think that motor, it was a longtime ago that I built and dyno that motor (it made 727 HP in Klamath Falls, OR at 4300 Ft above sea level) that 9.99 run was with a set of CNC ported 440-1 heads with an Indy 400-3 intake with Wilson 2.0 inch tall anti reversion space with a stock Holley 9375 non HP 1050 CFM Dominator.
That car and motor exceeded my wildest hopes regularly boogie

Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)