Master cylinder from single piston brake car on 4-piston car?
 

Recently the brake master cylinder on my FC (5-lug, 4-piston front brakes) went out. I was in the middle of replacing it with the master cylinder from my other FC (4-lug, single-piston front brake car), when I remembered that people often recommend swapping master cylinders when doing 4-to-5-lug swaps, indicating that the master cylinders may be different.

Will I be okay running a single-piston brake MC on a 4-piston brake system? I'm not really concerned with optimal performance, since the car is a beater anyway, but will it work safely?

I doubt whether the attachment points on the MC for the metal lines will match up.

It will bolt up, but I was wondering if there was some obscure difference between the two (piston size, piston stroke, etc). Looking at Mazdatrix, they make no distinction between master cylinders for single-piston front and 4-piston front cars, so it looks like I'll be good to go.

Most commonly the cylinder bore size is marked on the master cylinder somewhere. if they are both the same and all the lines match up then you should be fine. I've never looked at the two next to each other and see if they were the same. Good luck


Zack.