Got a question.. First I'm installing a 13B Street-ported 4 port in my 80 rx-7. Which flywheel/clutch/pressure plate combination can I use? I'm keeping the 80 tranny for now..


Thanks, Steve..

 

right now i am running stock stuff for all of that. but hope to move to a series 2 tranny, rb light steel flywheel (something like 17lbs). not sure what clutch/pressure plate yet though.

i know that is not what you wanted to know. but just thought that i would let you know that the stock setup does work, well enough, for that engine

(by the way, where did you end up getting your engine from?)

 

Flywheel - whatever goes with the 13B.
Clutch - whatever goes with the flywheel. (215mm or 225mm)

The stock tranny will work as long as you're using an N/A clutch.

 

thanks

 

I have that exact setup:

80 chasis, 1974 4-port 13B, weber 48 IDA, centerforce street/strip cluch.

illuminas, tokicos...the works.

she goes zoom.

 

Gonzz, if you promise to autocross it and fax results to them, go to mazdamotorsports.com and check out the aluminum centerforce flywheel and all their clutch options. Peejay is right on with sizes. I'd strongly reccomend the 225mm clutch since it's more widely available. And it should grab better (larger diameter, more swepth path). Yeah it weighs a tad more, but that's negligable compared to the weight you'll save with a lite flywheel!

I think you can register with them online now too.

-bp-

 

"grabbing better" is not necessarily a property you want with a clutch. stronger is not always better. if the clutch doesn't slip down when you launch, then either the tires spin (which is less controllable) or drivetrain parts get shocked and will sooner or later break.

plus, i could definitely tell the difference between a 215 and a 225mm clutch as far as shiftability goes. there is more rotational inertia that the synchro has to deal with with the larger clutch. the clutch disc is still attached to the input shaft when you disengage the clutch and is a good portion of the inertia that the synchro must deal with.

 

So peejay you're saying going to a 225mm clutch will break his drivetrain?

Going to a double solid disk Borg and Beck clutch certainly would, but he's not going in that direction. Is that what you mean?

The rotational inertia makes sense but it really doesn't sound like a big deal. I don't see 1st genners all running out and converting to 215mm to save the trans. It's only 10mm dia more! The clutch and flywheel options and replacements for a 225mm are better.

-bp-

 

No, probably won't, but the 215 has its advantages

I had no problems with the 225mm stock clutch. I *preferred* the 215mm. Either way, it didn't slip enough for best 1/4mi times, and the hydro clutch really robs the feel so it's super hard to slip the clutch "just right" for a good launch.

 

thanks guys..