TomP, I'm almost positive you know the answer to this.

I'm having some flywheel issues( with my PITA T5 swap) and I wanted to know the difference between an 86- earlier and an 87-up flywheel. I have 1 of each, my '85 flywheel has a fat weight on the back and my '88 doesn't.

Sooooo, are the early 6ers externally balanced and the later ones internally balanced?????

 

I have a 92 5 speed. No weights. Neutral balanced.

 

Yep, you got it, Dan. 1987 was when the 2.8's in the front wheel drive cars received the distributorless ignition, and used an extra crank counterweight to hold the timing signal. The '87 rear wheel drive 2.8's inherited the counterweight, but stayed with the distributor. The counterweight allowed GM to internally balance the engine.

So 82-86 2.8's are all externally balanced on the flywheel. All 82-92 2.8/3.1 (and maybe the 93-95 3.4?) balancers are neutral balanced.

As to what you should do, I have no idea. Let me know what you come up with, though!!

 

Thanks guys. I guess i'll be using the '88 flywheel I have. The '85 will get junked unless anybody wants it........