OK I have recently build a temporary S4 motor for our racecar.



I want to use the Tilton 2 disc clutch and flywheel that was on the 74-85 13B motor which was in the car before, my question is: Can I use the 74-85 rear counterweight for the S4 motor with stock internals?



Kim

No. You need an s4 counterweight.

Never heard of an S4 CW. Who sells them?

Off an automatic trannied car?



I've got one sitting here, but it's for an s4 turbo.



Hmm, now I'm second guessing myself. I was comparing an early 13b rotor to a s4 turbo. There was nearly a pound difference.



The counterweight must match the rest of the rotating components.



Maybe this will help. http://www.mazdatrix.com/faq/rotorwgt.htm

K thanks heff.

Ill go order one at Mazda

i believe there was auto turbo's in japan, some verts if i remember right. I'd check with a place that imports j-specs, im sure they'd have some laying around. call jeff at www.mazdaracing.com , he had an extra for my s5 turbo.

I live in Europe, im sure that shipping/handling makes it cheaper for me to get a new one instead :(

I had s5 tii rotors in my engine...when i rebuilt i went with s4 tii rotors. I had to buy a rear CW from Mazda cause i have an aftermarket flywheel.



Best 90 bucks of my life :( But still cheaper than the folks at act clutchs. I think they wanted 150 OO



James

NA and turbo are same weight rotors between same series