Looking for a RX7 flywheel ('79-'80 the big heavy one...)

So I've been daily driving my 1985 RX7 for the past 4.5 years and 90+k miles. The inevitable happened and the 170k 12A finally coughed up an apex seal. No worries, I have a spare engine of a fine SA vintage but no flywheel to match. The scary thing is the flywheel in the car is an '83-'85 (car is an '85) but the engine in the car is a '79-'80. So I've been driving around all this time with the wrong flywheel... So if anyone near SE Michigan has the fatty '79-'80 flywheel they would like to sell or trade me please let me know.

I have a '79-80 flywheel somewhere. I may also have a '81-82 flywheel, which will work just fine as '79-82 all used the same rotors, and the '81-82 flywheel is MUCH lighter.

Bear in mind that you can NOT use your existing clutch, if you weren't aware of that. The pressure plate heights are vastly different between the 215mm and 225mm clutches and while you can use a 215mm disk with a '83-up flywheel (have done it, no problems) you can't put your disk on an early flywheel.

Can't access for at least a week, stuff is in borrowed storage.

I'm also surprised that the 12A died so early. Must have been abused to not make it to 300k.

300k on a 13a. Really?

In reply to markwemple:

I put 280k on my 83 before it spit the rear apex seals. A 12a will run a long time with minimal issues. Keep it cool, keep it lubed, and spin it over 7K rpms at least once, every time you drive it.

I have a 83 flywheel, but nothing earlier.

Thanks Knurled for the heads up on the clutch disc size difference. I forgot about that. I lucked out and picked up a flywheel from a local Lemons team today. Back in business as soon as I get the right clutch kit. Strange thing is the "blown" engine seems to have all it's apex seals, at least what's visible through the exhaust ports. Compression was 30-30-90psi on the rear rotor and it was 110psi across the board a couple weeks earlier. Maybe the apex seal is wiped out at the corner where I can't see it.

In reply to RXBeetle:

If it still has 30psi compression, the apex seal is still intact, or at least mostly there. The spring might be flattened or the corner piece worn to a nub.

Sadly, it seems like 12As die by eating rotor housings first and cheaply replaceable parts second. I'm interested in the dead engine if you don't want to keep it for yourself.

I have a 79-80 flywheel. Let me get you a picture.