I had a 66 Nova, with drum front and 9" Ford rear drum brakes, it ran mid to low 10's also with a single master cylinder, it would lock up the front wheels in a heartbeat. In fact i got disqualified at a race when the throttle linkage stuck on the tunnelram manifold, and i stupidly hit the brakes too hard after the finish line blowing out the left front tire. I stayed on the track but the track operator still put me out even though it was after the qtr. mile. I ran the car for 5 yrs and never could get it to stop hitting the front brakes harder than the rear. Maybe changing out the masterclinder to a duel master cylinder might fix it but i never tryed it.
Zip.