That Demon has huge wheelwells in the back. Like my 68 Barracuda.
I installed 235/60-14s on the front with the same brakes as yours. On the back I installed 295/50-15s. With 10 x 2 drums, and NO proportioning whatsoever, and some big W/Cs back there. Now the back brakes awesomely, and I don't have to lock up the fronts anymore.
But to be fair, My driving is 100% street,
and ~99.9% of it, is at less that 65mph/5600rpm.
Second gear tops out at 6500=75mph, to 7200=84.lol
