We supply with stock side seals (Mazda) that are made oversized. This is done because your side seal length will vary depending on manufacturing tolerances of the rotor. You need to carefully grind them to length, giving a TOTAL clearance of 0.002 to 0.006 between the side seal and the corner seals. Methods are discussed in the instructions included with your kit and the Haynes manual.

HELP!  I installed  your o ring kit (or overhaul kit) and I have EXTRA O RINGS left over. What did I do wrong?

A. The O ring kit (which is included in the Overhaul kits) are UNIVERSAL (to fit 1986- 1995 engines).  Because of this, we include 2 different oil cross over rings.  You only need to use the ONE that fits your engine year.  Also, we include the INJECTOR DIFFUSER O rings and CRANK ANGLE SENSOR o rings in the kit.  Many builder's forget to replace these O rings and are a common cause of "extra" O rings.