so attempted to do the auto to manual trans swap today...

12a motor, 12a counter weight, 13b clutch and flywheel, first gen 13b trans.

so someone just laughed at me. the early frist gen 13b trans uses a smaller clutch then the second gen rx7's don't they?

so my question is.... will a secound gen trans mount to my 12a. or do I have to get a different clutch and flywheel. I would prefer to get a trans as I have no idea about how good the one I have is, and my brand new clutch is mounted and tqed to the 12a.

 

ive tried that one before the second gen tranny will bolt up but the trans crossmember ends up too far back unless you swap the tail housing to the 12a one or do what i did and weld it in place

 

the NON turbo FC trans uses the same clutch/flywheel as the 83-85 cars. the 82 and earlier cars use a smaller disc and pressure plate, but same flywheel diameter.

the TURBO fc's use a larger flywheel/cltuch etc etc.

 

so you are saying I must have a turbo clutch.........fffffffffffuuuuu this just got more expensive.

I have a 84 fb trans and it does not clear over the clutch, so that means I need a turbo trans.... does a turbo trans bolt to a 12a?

I very right now I thought I had this figured out.

 

the turbo trans will bolt to the 12A fine but if you use a second gen turbo trans you will need to modify the shifter to fit in the proper place and get a driveshaft to adapt the turbo yoke to the first get pinion what year car and parts do you currently have?

 

If your using all stock parts, do not use a 13b flywheel with a 12a motor. That's a big no-no. You must match the flywheel with the engine rotating assembly/year of the engine. It will fit, but the weight is wrong and will destroy the engine over time. The 84 13b trans will wotk just fine.

This site will tell you the correct flywheel and clutch to use for you engine.
http://www.mazdatrix.com/faq/flywheel.htm

What year is your car?

 

no its a aftermarket flywheel on the org auto weight. I did do a lot of research when getting my parts, and bought a whole 84 glse with a blown motor for the trans. the eaby sale said the kit was for a 13b.... apparently a 13bt
now I need to buy a turbo II trans or a different flywheel clutch. so pissed.

 

I'd buy the correct aftermarket flywheel. I think the clutch will work. It will be the same 225mm as the 13bt. Even with the 1984 trans, you will need to fab up a crossmember. I don't know enough about the shifter location on the TII to know if it will line up with the shifter hole on the tunnel. I did the auto to manual swap with all 12a stck parts and had to fab up this plate for the trans mount. (I have a couple extra holes by mistake)

 

so sell the flywheel and get the right one, and be done

 

I think this will be the plan.

 

the turbo R type gearbox clutch he has is 9.5 inch with 23 splines with a 330 mm ring gear

the 12a M type gearbox wants to see the 300 mm ring gear 8.5 and 9.0 clutches with 22 splines for the input shaft

he can get a 300 mm ring gear flywheel
- which take either the 215 ( up to s2 ) or 225 ( s3 and s4 NA ) clutch setups
,, but he will also need a 215 mm clutch disk in 22 splines and the correct 215 or 225mm cover pressure plate


alternatively he can buy an R type turbo gearbox ( and starter )

shorten the shifter assembly 103mm ( for s1 and earlier cars ) ,
or swap on the 12a shifter housing ( for s2 and s3 )

and he will then require a custom slip yoke end on his existing tailshaft ( or a custom shaft )

 

ya, I just ordered a clutch that fits. ebay gold. will see how that works out. the last clutch I ordered was a steel flywheel and a kevlar sprung clutch it was a quality unit and it sucks that I cant use it. this one is alum flywheel (witch I don't like) and a 6 puck ceramic non sprung, Lucky for me the car is mostly a track toy/weekend warrior, but its a combo I have never tried, and am a little eh on, but I couldn't afford to get a steel flywheel combo that I liked. sometimes you just got to take risk.

 

Oh btw I test fit the 84 trans with out the fly-wheel because of this post and it all bolts up fine. 1982 12a car, 1984 13b trans and cross-member just had to use the set of bolt holes on the car that were unused with the auto-trans. no need to make a custom trans mount. and the clutch wont work had to get A whole different setup.

 

puck is fine on a race car, but you want a sprung hub. the sprung hub is easier on the trans/rear.

 

well in typical ebay fashion what I got was not as pictured. its a sprung clutch not a solid center like the picture......... all in and I put 300 miles on today Sooooooo! much better then a auto. lol

still have to wire in the rev lights, and I think all 3 motor/trans mounts are screwed but it drove great. 6 puck its a little rough, lucky for me I live in a very rural area so stop and go, is a rare thing around here. it is street-able but its tricky to take off if your not launching. so if you live in the city don't get one.

 

Nice to hear the 1982 car has both trans mounting points. I'm not sure why Mazda changed the 1984/85 body to be trans dependant.

 

I believe it was due to the 84/85 having an overdrive trans the mount was moved back for clearance. my car was an auto (85) I had to make a plate from my crossmember to the turbo trans mount.