11” drum wheel cylinder bore size question.

There is also a 7/8” bore wheel cylinder that works with the 11” brakes. It can be used to reduce the braking power a bit to balance things out if the 11” drums lock up too early. Kind of similar to using an adjustable prop valve to balance the brakes out.

Whether or not the 15/16” or 7/8” will work better for you though depends on how your car is set up for suspension, tires and weight balance.

I swapped 11x2.5’s rear drums onto my Challenger with 15/16” wheel cylinders, they were a little much until I upgraded the front disks from the stock 10.95’s to the later 11.75” disks. After that they were fine.