are the 2nd gen 4 piston calipers reversible or is there a left and a right caliper? i did a conversion on my 1st gen and the passenger side caliper holds the rotor tight i cant even push the car. the driver side is tight but not as tight as the passenger. does it need to be bled more?

 

Not reversible, brake hose connections. The 4 piston calipers have a tendency to have the lower pistons "freeze" up as condensation settles to the bottom of the caliper. If they are that tight, and not an internal break in the hose, you'll need to rebuild. Loosen the bleeder and see if the piston(s) can be pushed in easily. If they move in easily with the bleeder open, replace the brake hose. If still tight, rebuild or replace. Fairly easy to rebuild if you have the time.

 

Make sure the bleeders are facing up. Not reversible.

 

ok i just switched em around i had the calipers in front of the rotor and just placed em behind the rotor with the bleeders on the top side and brake hose coming in on the top side of caliper now both sides are really tight. how hard is it to rebuild? and where can i get a rebuild set?

 

also how do i center the caliper? the two inside pistons are closer to the rotor than the outside.

 

The brakes will center themselves when pressure applied as long as the pistons are moving freely in their bore and the pins are clean.
Mazdatrix:
49-2400-FB05 $32.40

Rock Auto
BECK/ARNLEY Part # 0717798 $14.45
DORMAN Part # D352001 $6.80 p/side-$13.60
ACDELCO Part # 18H167 {#18031641} $16.13 p/side=$32.26

Hardest part about the rebuilt is to get the pistons out. I use an air compressor with rags inside the caliper to protect the pistons when they come out. If one is stuck, I'll use a piece of wood between the other 2 to keep them in place while the air pushes the tough one out. When out, just clean up the bore and pistons, remove all residue, lubricate and install.