Is there any way i can tell an FD oil pressure regulator from an FC regulator? Besides oil pressure. reason why im asking is becuase i have a rebuilt shortblock and want to shim the regulator, but shimming an FD reg would probably make to much pressure? is there any cosmetic difference, markings, etc? i have complete access to both of them and i cannot start it to look at oil pressure.

 

They look pretty much identical once off the iron/motor they came from. The FC always has the lower spring tension, if you have 2 and are trying to compare. Otherwise, I dont know how you'll tell.

 

turbo II one is a max of 60psi to bypass and i think the FD is 110. check mazdatrix i think they got pics of both in the and BTW it fits on the turbo II engine

 

^^^^ Read posts much? He's not asking what they flow.

 

You need a spring pressure tester or something to the equivalent that can measure spring pressure over distance.