I was typically a 1.56-1.59 with my 78 Malibu running the BMR bar, 10.57@125mph. Foot-braking at 2500 rpm.
I switched to the TRZ ARB, and my 60 is a best of 1.44, 10.49@128mph. Took out about 70 pnds and transbrake launch at 4400 rpm.
I'm sticking with the ATR 1 3/8" bar on my GN for street duty.