I think that I might have got myself into a jam here. I recently purchased a lightweight steel flywheel off of e-bay. Originally, the application listing stated that the flywheel would work with my 1990 N/A RX-7 with the 5-speed manual transmission. Upon receiving the flywheel, I noticed that it came with a separate counterweight, which I wasn't expecting, since the advertisement seemed to have mentioned that it would install directly on the end of the e-shaft. I did some comparisons, and found that the flywheel is 12.5" in diameter, with a 240mm outer diameter on the friction surface surrounding the hub. I found that it is obviously meant for a turbo application, since the N/A version is only 11.75" in outer diameter. My question: Is there any way that I can make this flywheel work with my N/A engine and manual transmission? I have a hunch that I may have to change to the 13-tooth turbo starter, but I will have to retain the N/A clutch disc due to the 22-tooth splined hub that will fit onto the input shaft of the transmission. Problem is that this clutch disc is 225mm, which is smaller than the 240mm disc that goes with the turbo version.

 

I'm gonna say no. I think even with the turbo starter it's still going to be in the wrong position due to the difference in flywheel diameters. I would try to return it. If the seller won't take it back you could try to sell it and get a n/a one.

 

Thank you for confirming this. I had my doubts when I took the new flywheel out of the box. It's amazing what can be learned with a little research. I found that the turbo flywheel has 125 teeth vs. 116 for the non-turbo version, and that the turbo starter has a 13 tooth pinion compared to a 12 tooth pinion for the non-turbo. I also viewed someone selling a bell housing to a turbo 5-speed transmission on e-bay, and noticed some differences. And, it soon donned on me that the larger diameter of the turbo flywheel means that the starter mount on the bell housing would have to be in a different position in order to mesh properly. I have started the return process, and hopefully can get my money back. After this, I'll just have to cough up the extra $$ to purchase a lightweight flywheel from Racing Beat. At least RB clearly advertises the two different flywheels, so I know how to get the right one!

 

You're welcome. I'd have to do some research but at this point in time I think RB may be to only people making non-turbo flywheels. It's probably safe to say any brand other than Racing Beat is for a turbo.