Miata Transmission Differences

[mbuskuhl]

Is there any difference between the 89-93 and 94-97 Miata transmissions? Is the gearing the same?

I know nothing about Miatas, only RX-7's.

Thanks!

[ddewhurst]

'M' gear ratio's

Car
1st
2nd
3rd
4th
5th
6th


79-83 RX-7
3.674:1
2.217:1
1.432:1
1:1
.825:1

RWD 626
3.214:1
1.818:1
1.296:1
1:1
.858:1

84-85 RX-7
3.622:1
2.186:1
1.419:1
1:1
.807:1 12A
.711:1 '84.5-85 13B
.758:1 '84-84.5 13B

86-91 NA RX-7
3.475:1
2.002:1
1.366:1
1:1
.691, 86=.711

Miata
3.136:1
1.888:1
1.330:1
1:1
.814:1

'85+ B2000/2200
3.622:1
2.186:1
1.419:1
1:1
.858:1

99+ Miata 6-speed
3.76:1
2.269:1
1.645:1
1.257:1
1:1
0.843:1

The main focus is the installation of the 94+ Miata MX5 gearset, making a relatively close ratio box. Although the earlier Miata transmissions use the same ratios, a dual cone synchro was introduced in 94. With the current age of these cars, used transmissions are readily available so there's no sense using a pre 94 gearset. Quicker cleaner shifts, more time spent closer to peak HP, and fewer shifts in turns are the only advantages to using the Miata gearset. It's no stronger and no more reliable than the FC gearset.

[mbuskuhl]

Looks like you know what I am doing :cool: I just found that gear chart but had not seen the text you posted. Thanks!

**NOTE...I know it's not IT legal but I run ITE**

[ddewhurst]

If your in need of the shaft rework dimensions you can look at the mazdatrix site or I can forward the dimensions to you.