Caliper Choices

[toomany]

I'm at the point where I need to pick up some calipers for my project. Question is, which would I be better to go with. The JB6's or the JB7's.

I'm running a 24mm (.944") straight bore manual master cylinder. Both the front D60 and rear 14B will be using the same 3/4ton style rotors. I already have a set of Jb7's that I know are good. I've got a questionable set of Jb6's that I planed on using for a core on whatever I buy. Being each wheel has the same rotor and master cylinder pushing it, I figured it'd be a good idea if the calipers matched.

So, which suits me better? The larger Jb7's at 3 5/32" or the Jb6's with the smaller 2 15/16" pistons. Will it even matter much in my application if they aren't matched? FWIW, the truck will be have locked axles and be in 4wd 99% of the time in the mud.

 

[paratrooper307]

You don't need to match calipers on the rear. Look at most stock disc brake systems, the rear calipers are always smaller because they carry less of the braking load. Bigger calipers on the back just means more fiddling with brake proportioning to prevent rear wheel lockup. Are you using one of the 14 bolt disc conversion kits? I'd go with whatever fits the kit or is recommended. You're likely going to need a different proportioning valve anyway, since the factory one is calibrated for drums. Some other members will likely chime in, but it seems disc brake conversions on the rear are somewhat of a mixed bag.