Flywheel question and about counterweights..
 

Ok.. Heres the deal. I have an automatic 3rd Gen RX-7 and Im doing the auto to 5 speed swap.. I have read and heard around that you can not use the stock 5 speed flywheel in this swap due to the counterweights that are on an automatic. I think the auto 3rd gens have 3 counterweights. 1 in the back and 2 in the front? You remove the one in the back though. Keeping the front counterweights there, I was wondering about the lightweight flywheels.

The thing is, I hear you can use the stock 5 speed flywheel in the swap IF you get it resurfaced or lightened. So meaning the lightweight flywheel weighs less so the counterweight is fine where it is.

What exactly do the countweights do? Is there a certain weight total needed for the flywheel to work properly? So the counterweights on a lightweight flywheel are to balance the weight from the light flywheel? So say u get a 9.5lbs flywheel the counterwight probs weighs 6.5lbs to make it add up to the same thing? like say the flywheel was 11lbs, would the counterweight weigh 5lbs? Thats saying the weight must be 16lbs. Im confused about this.. If I got a lightened flywheel, how will i know if it will work fine with the automatic counterweights?

Thanks and any info is appreciated.

Go with the lightened flywheel...
Since you are starting with an auto trans, you have the proper counterweight already.&nbsp It's just a matter of bolting THIS counterweight onto the new lightened flywheel and slapping everything back.

If you go with a stock flywheel, you'll need to remove the automatic counterweight you already have in there.



-Ted

The counterweight has extra weight that is not only there but must be in a particular place relative to the eccentric the rotors and front counter weight. I have had engines balanced and while I dont truly understand all of the principles I can assure you that it can be the difference between a good and a very ordinary and unreliable engine. RETed is spot on with his advice, perhaps you may want to have the flywheel and clutch assembly independantly balanced aswell.
Regards- Anthony