I know these questions have bounced round before but I can't find the answers I need in the archives. So if you do not mind.....

I am reassembling the engine for my SA22. I have heard that exchanging the 30 pound flywheel for a lighter FW from a later 12a can gput a little more spring in its step.

I sourced a 26 pound FW from an 84-85 12a (verified based on Mazdatrix FAQ page) but the guy is only 90% positive that the front counter weight is correct. I'd prefer to be 100% before putting the engine back in the car.

The counter weight is much smaller and shaped differently than the stock CW for my car. But, I cannot find any distinguishing marks or stamps on the thing and Mazdatrix FAQs do not describe the the CWs.

Can someone tell me how to tell if I have the correct CW?

Thanks,

Herb

 

you might want to post a photo of it. Jeff20B is pretty good at ID-ing counterweight on sight and he just may find this thread.


on an FYI note: why did you post this in the Build section?

 

The flywheel you got is wrong. Sorry to crap in your cocoa puffs.

Post some pictures. If you have the right front counterweight I should be able to tell you. And look for a 23 pound 81-82 flywheel. Look here again to see what it looks like. Flywheels

 

What is "wrong" with the 84-85 flywheel?

Will post pics when I get home.

 

Apparently the 84/85 flywheel and counterweight don't balance with the slightly heavier SA22 rotors, so you can't combine SA rotors with the later 26 lb FB flywheels.

However the even lighter early 81/82 FB flywheel (23 lbs) and counterweight do balance with the heavier SA rotors, which I guess were still being used until 1982.

For reference, here's what the 23 lb 81/82 flywheel and counter weight look like



And here's the heavier 30 lb SA flywheel and weight



And here's the 26 lb 84/84 flywheel and weight (also used in 83)