Master cyl. Dia.

[Elam Budmore]

What size front and rear cyl. dia. would comonly be used on a sportmod with gm metric calipers?

[UltimateRaceCars]

1" front and 7/8" rear

[drtrkr244]

Most builders are using 1" front and rear. Theres enough adj in the brake bias to get enough on the rear.

[mod71m]

I prefer 7/8" masters for both front and rear. I used to stagger them and use a 1" front and 7/8" rear but I find there is plenty of adjustment to get rear brake bias with the same size of master cylinder on both. Also the balance bar seems to work better and be more repeatable when both masters are the same size.

I like the 7/8" better than 1" so that you don't have to push as hard on the pedal to get the car to stop.