I'm going to replace my flywheel shortly, and I'm trying to figure out exactly what year flywheel I need to replace it with. The engine is a stock 12at. From what I have found from searching, the 12at's were put into RX7's from 83-85. The flywheel that is on the engine now is from an 82. It seems to have been running fine so far. I was just trying to figure out if I need another 81-82 flywheel, or should I get an 83-85?

 

Is your car an actual RHD Japanese import 12aT with the orange fan and everything? Or is it just a 12a with a turbo on it that you *think* was like that from the factory.

It will definitely make a difference. 12a Turbo cars were not sold in North America at all, so unless you have a Right-Hand Drive import, you're probably looking for just a regular 12a flywheel.

Jon

 

This is definately the 12aT import from japan. Complete with orage fan and intake.

 

'83-'85 flywheel or counterweight should work.

 

An 82 flywheel is the lightest stock flywheel you can use, anything else witll be heavier. See this link for the flywheel identification and weights http://www.mazdatrix.com/faq/flywheel.htm. Not sure what they put on a 12aT so your mileage may vary. I grabbed one of these from a guy on ebay, but he never had it advertised in an auction, I asked him if he had one. PM me if you want the info. It was only 60 dollars and I had it resurfaced and just dropped it in. Looked perfect.

 

Nice info, bad advice. While the 82 flywheel may be lighter, it is not balanced for the 83-85 rotating assemblys.

 

DOH! Good call. I knew that but it plain left my head when I replied.

Hmmm, but he already has an 82 on it, so he says. Wonder how that happened? Somethings not right here.

 

If somebody really does have an '82 flywheel on an '83-'85 rotating assembly, it works probably without any noticeable vibrations, but when teardown time comes, the stationary bearings will look awful.

I think the original bad piece of advice came from the Mazdaspeed site.

 

that is/was intended for roadracing where you cant port, but can mix and match parts, so you want the 81-82 CW and flywheel with the 83-85 rotors, as this gives you the lightest rotating assembly, however it does need to be balanced.

 

Ah, that sounds about right. Thanks for clarifying.

 

Thanks for the info! I was wondering if that was going to be a problem or not.