I have an 85 gsl rx7 i just recently bought and earlier 13b motor. from what i was told it came off a REPU. Ive already got the gsl-se oil pan and wanted to know does the motor just go in to the stock 12a tranny? and can i use the 12a flywheel? or a second gen? (flywheel i have one sitting around)
thank you for reading

 

I'm not sure about the engine/tranny I think it should bolt right up tho. What I AM sure on is that you can't use the 12a flywheel on the 13b regardless of size because the rear counterweight is cast into the flywheel.

 

I got a tranny with the motor but it looks just like the one I already have on the car. About the flywheel I had a feeling. Thanks. I know the 13b is an older model 13b cuz it has an oldschool Mazda imprint on the housing. Any 13b flywheel should work?

 

welcome.

what's the issue with the flywheel on the engine now?

at any rate, you need to keep the flywheel matched to your rotating assembly.

 

I got the motor with out a flywheel so I'm stuck. I have a 13b flywheel but it came off a 2nd gen.

 

i know the 12a tranny be no problem bloting up w 13b.. same set up i got but you will need the fly wheel on 13b fb .. second gen i think be diff.. easy way to check it look up the parts spec see if matchs up

 

since the engine didn't come with a flywheel, ur best bet would be to get a light weight flywheel with counter weight from RB, Mazdatrix, etc. chances of u finding a stock one for that engine will be slim. bolting it to the 12a tranny will be no problem.

 

I checked the Mazdatrix website and it says that you will need a 1984-85 13B N/A flywheel.

 

Cool thanks alot guys for the help. I'll look into the light weight fly wheel. But would I need the flywheel for a 70s REPU 13b or just get the GSL-SE one ?

 

Good question, are you positive it is from a 70's REPU? I would think that yes you would need one from pre-80's.

 

I'll try to double check I know for a fact it's from an older car. The mazda sign on the top of th housings are old school.

 

if you can't say for sure that the engine has never been opened/rebuilt, then the fact that you have old school housings means squat. you need to know what rotating assembly you have.

is it possible to get any accurate history on the engine from the previous owner?

 

It was rebuild before and then just sat for awhile. My friend rebuilds these motors. From what he saw he said it had GSL-SE. Rotors it also had a street port and the guy I bought it from mention a half brige port. We also where able to check the compression on the motor sound strong. So that's what I know. And I'm just trying to get this thing going. Thanks

 

well, then you need to get an SE flywheel or aftermarket flywheel for the SE. you can check the Gen I classifieds for both.

 

If the internals (rotors) are from a GSLSE then you can use the 84-85 N/A flywheel but if it really does have a bridge port it would be a smart idea to go light weight for your flywheel. How did you check the compression, in the car or out?

 

My friend would rotate the rotors. By turning the bug bolt in the front of the motor and should good compression. And thank you guys for the help/info on the flywheel. I got a better idea of what to do.

 

Yea thats the way to check it out of the car. There should be 3 even pulses per full rotation of each rotor. If they are uneven sounding then there is an internal problem.

 

Cool yeah they sound pretty good. Thanks alot guys. For all the help I found GSL-SE flywheel for 50 bucks I'm a pick it later tonight. Once again thanks for all the help guys. Can't wait to get this car going.

 

Youre welcome Im glad I could help and goodluck with getting your FB running. I am in the same boat right now with my vert.

 

What u trying to do ?