How to install PPF frame on a MX-5 NA/NB/NBFL

Countless customers have already removed their transmission on their MX-5 NA/NB/NBFL themselves. Be it to replace the clutch, to replace sealing rings or to replace the gearbox. But many do not know that after the transmission installation, the frame between the transmission and the differential has to be adjusted correctly in order to avoid unpleasant noises from the transmission and the differential. In this blog you will learn how to do it right!

After the gearbox has been flanged and fastened back to the engine, the PPF frame can first be put back on the gearbox. The screws can already be applied, but should not be tightened yet. The wiring harness can also be attached to the PPF frame and the conectors can be plugged into the respective sensors on the gearbox.

Now we move on to the official Mazda instructions on how to adjust the PPF frame:

First, as a measurement reference, a squared bar should be placed on the left and right of the longitudinal bars, which run from front to back on the left and right of the vehicle. The distance between the top edge of this bar and the bottom edge of the PPF frame (A) should be 60-72mm. When this distance is reached, the 3 screws from the PPF frame to the gearbox can be tightened. Mazda specifies a tightening torque of 120Nm for the longer screw. The two shorter screws that are screwed into the gearbox from below should be tightened to 50Nm.
Important note for all users of CAE or CoolerWorx Shortshifters:
It is better to choose a smaller distance between the measuring bar and the PPF frame so that the shift gate has more space to the center tunnel and the shifter cannot hit the center tunnel.

This predetermined distance avoids tension in the drive train, which can cause unpleasant noises. With the correct distance, noises are reduced and noticeably more pleasant.

After you removed your transmission, did you also have noises that you couldn't hear before? Feel free to try the adjustment of the PPF frame and give us feedback if the adjustment according to Mazda specifications worked! Feel free to leave a comment for your feedback as well as any installation guides you would like to see featured on this blog.

Your SPS Motorsport Team