The master cylinder I took off my friend's '86 was 7/8" bore, the V6 master was 15/16" diameter. (Corrected per Kevin C's post) Usually, the size is cast onto the side of the cylinder itself. Look at the one that's on the diesel to see if it's the large or small version.

Last edited by MartySoCal; 01/21/10 02:02 AM.