7.25 to 8.25 swap? /6 to 318 swap?

Myswinger said

I don't mean to thread jack your post but I've got a question! 1970duster I am putting together a 72 swinger I just picked up its a factory power front disc brake car and the thought of rear disc interests me greatly the previous owner had already swaped in a 8.25 so that's not a problem my question though is when you do the rear disc swap do you have to run a adjustable prop valve for the rear????? Sorry again OP I had to ask!

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Okay I got a question for you. Do you have the single piston calipers or 4 piston calipers? The single would mean you (should) have the same bolt pattern front and rear 5x4.5. If you have the 4 piston caliper it would mean you have the 5x4 bolt pattern. I ask this because the 8.25 rear only came as a 5x4.5 big bolt pattern.

To answer your question there are two ways to do it 1. Install an adjustable prop valve (highly recommended and the way I'd do it), 2. Use a prop valve from a 4 wheel drum brake car (while this will work I personally wouldn't do it that).