Morey987

Anyone know where I can get a good set of adjustable cam gears?
Hehe, totally kidding! I always love that one, never gets old.

Anyways. I have a 4 port 13b from Rotary Engineering in my 79 and I am looking into a new flywheel and clutch setup. I don't know if it's 215 or 225mm. Does it really matter as long as I get the appropriate counterweights and entire setup together. I mean, can I change TO a 225 with the right counterweight and matching clutch?

Rx7carl

According to mazdatrix, 74-82 is 215mm, 83 up is 225. What year 13B will tell you what you need. Be careful, your engine might be a later 13B with 12A irons.

http://www.mazdatrix.com/f-writng.htm

Morey987

Will that matter if I have 12A Irons? I figured it would just be the rotating assembly that would matter. Is there a benefit of swapping in the 225? I guess I just assumed bigger is better. I guess the problem is I want to upgrade and I don't want to buy ONE wrong piece. I'd rather just buy a flywheel counterweight and new clutch to make sure everything is right. And from what I've read as long as I swap in everything from ONE setup and use the correct counter weight it'll work. But I don't want to buy everything and have it all be wrong either!

Rx7carl

Thats what I mean. It could be early or late 13B internals. If you use the correct CW I dont think it matters. Look at the parts list. For the bare FW they are all the same.

http://www.mazdatrix.com/flywheel.htm

Morey987

Cool,,,,,, anyone know how in the hell I am supposed to tell what internals they are?
It's a Rotary Engineering motor built in 86.

dean7

I can prolly help, buddy has a 82 w/ the same engine as you from the same place, bought used. Its prolly a REPU (rotary engine pick up) engine. If you can afford to drop your transmission (shouldn't take any time at all if you've done before) measure your clutch... I'm guessing that it might already have a lightweight flywheel in it, unless you have taken the transmission off, I think it would be a bad Idea to order any part.

You prolly don't know what kind of transmission is in your car right? Anywho if you measure the clutch, you'll know what one to buy as all NA cars up to 88 or around have the same setup, except for going from 215 to 225 in 83.

About the internals, just use this page (link off of the page Carl7 gave you) http://www.mazdatrix.com/faq/Rcounterweights.htm to find out what they have done to your internals (should match with the front counterweight)... This is if you have a lightened flywheel in the car, witch I have no idea if you do, maybe not..

Also, if you changed your clutch size from a 215 to a 225 wouldn't you need to modify the transmission(bell housing) not sure though, just thought Id mention it... If what I am guessing is right, I think that the car has a 225mm clutch in it allready... But if it doesn't, im not sure if you can find out by checking the front counterweight. But I have seen recently in this forum, a post by jjbrozak, where they mentioned how to tell the difference between some stock flywheels.

Hope I was of some help

Morey987

Yeah, I have done plenty of searching, and I have done plenty of wrenching on these wonderful little bundles of joy before. When I get back to her I'll tear into her and see just what I'm dealing with. Thanks for the info though! Hopefully she already has one. That makes things that much cheaper!

dean7

Also, if it is a stock flywheel.clutch.. If its a Repu, it will have 9 bolts going through the pressure plate to the flywheel. If its an rx-7 set up it will have 6.

Morey987

Wil an rx7 setup swap right in? Why can't this thing just be semi normal! Hehe