dssur
+1y
mazdas have an open rear differential, so you have to rotate the wheel TWICE. The open wheel takes half the revolutions (sometimes its not exactly half, sometimes it rotates 1.3 on the drive wheel and .7 on the open wheel) so you can either:
a) leave one wheel on the ground when you turn the other and count the revolutions of the driveshaft or
b) rotate the wheel twice and count the revolutions of the driveshaft.
Your count of 2 indicates a rear axle ratio of 4:1, which is very close to what it should be, the mazdas all came stock with 3.90 rear gearing. I have heard the earlier pinion is lower, but as to whether it bolts in or if it will be strong enough for a V8, I dont know.