Will a miata 4.78 Rear pinion gear fit in a TurboIi Diff?
 

i'm trying to tighten up my gearing and asides the Rx8 4.44 and 4.77 Rears what other rear ends with above 4.44 will fit in the TurboII Rear end? i was wondering if the miata 4.78 will Fit inside?

Mazda has two differentials (that we care about).

the P type, which is used in all the RWD V6 or turbo cars. the turbo 2, FC, Rx8 (mpv,929 etc) use this type. it has an 8" ring gear.

the M type is the other one. its used in the RWD 4 cylinder cars, like the S2000, 94-05 miata, R100/Rx2/3/4/5/7. the Na FC uses this type with a long pinion. the M type has a 7" ring gear.

i have a turbo ii rear and a rx8 4.44 gear and pinoon currently but i want to tighten up my gearing more, but not wanting to spend $2400 on 5.12, so im trying to see if anyone else has tried other options, the info you gave me is quite helpful, gives me an area to start looking at their rear final drive, thanks

the 09 Rx8 has a 4.77...

yeah i know but the 09+ 4.77 are hard to find and the 4.44 1st gen rx8s are easier to find and under 200bucks, so its a good choice on a budget