does someone know if the bolt pattarn for 12a are the same as 13b
or are they compleatly different,,is it possible to bolt a 13b tranny to
a 12a ??

 

As far as I know it will work w/o any problem, I havent done it yet, but will be doing it soon, I looked at my 88 vert and my 85 12A trannys, and the bolt pattern looks exactly the same. The only really significant as far as dimensions on these 2 motors are the 2 rorotr housings and rotrors, they are wider. Also depending on what year FB/SA and what year 13b trans, the shifter and location of the shifter may possible be different...

 

GSL-SE trannies are the same as 12A trannies for the same years except the -SE had a bellhousing vent and a different (taller? shorter? i forgot) 5th gear.

SA trannies ('78-80) have a totally different shifter position, the shifter is part of the transmission on the SAs (you can fill the tranny through the shifter hole, makes it LOTS easier ) while all '81-up transmissions including turbo have remote mounted shifters that put the shifter further back, but the shift lever goes straight up instead of angling back so the only functional difference is the shift **** is lower and further away from the steering wheel.

 

cool,,i thought so,,thanks guys,,i'm going to install a 86 5 speed in
my 82 12a..

 

OK, hold it... You'll need to swap the shift tower and tailshaft housing to easily put a 2nd-gen transmission in a 1st-gen. The trans mounts are all different and the shifter's in a different place.

 

So,,i use the tail shaft,and shifter mount ?,,i haven't looked very
close, but these parts interchange ? on the transmissions ?
i 've seen somewhere the gear ratios of all gens trans.if the 86 is the
same as the 82 i won't bother with it,i'll just save it,or sell the 86

 

1982:

1st
3.674

2nd
2.217

3rd
1.432

4th
1.000

5th
0.825

Reverse
3.542

1986:

1st
3.475

2nd
2.002

3rd
1.366

4th
1.000

5th
0.711

Reverse
3.493


The 86 is too high geared for my taste. Only thing I'd like would be that .71 5th gear

 

Makes a BIG difference in cruising at 70+ on the highway...

 

Yeah, 'cause you have to keep it in 4th gear so the engine stays in its powerband

 

WOW,,thanks felix,,also i put the GSL rear end w/lsd,,disk's,,i have
no idea what the screws are in the rear end,,i'm pretty sure the rear
end came out of an 83 gsl,,i didn't look what year,,but made sure it
wasn't gsl-se,,to fit with no problem,,,so use what ?? 82,,or 86,
with the 83 rear end...wouldn't it still be somewhere in the middle
of the power band,,,i guess i should say,100 mph + easy,,,or no ??
because,now it's it cracks 110-115 no problem,,and it's off the line ok
too...are the newer model trans. stronger,built better,better parts,
then the older 82,,because mazda learned,and beefed up,,,whatever
as the 1st gen evolved,,,,to the 2ed gen,,,and on,, right ??

 

Nah, all the NA trannies are nearly identical.

 

yeah,,ok thanks man,,,i'll keep the 86 if i need it down the line sometime