rotaryken

Appreciate some help. New member here.

Have searched this topic on the forum and unfortunately a lot of data is either outdated or non specific. Haven't found the answer yet.

Have owned 2 fb RX7s as street cars and loved them.

This led to the purchase of our '85 GSL that we have converted to a LeMons race car. Have run 5 endurance events so far and the car has been a blast to drive. We have finished well in all the races (except one motor DNF). Two areas that need attention are the motor (another post) and the brakes. We are running the Brembo rotors and Carbotech C76 XP10 compound pads. We find that these are marginal and would really like to upgrade to a larger ventilated disc and better calipers.

We followed links on the forum to CPracing, Selecmaz, REspeed, JMD, and Rotary Shack without success.

The braking rotors, calipers, pads, master cylinder, bias are all a system. So my question is where should we start? Aftermarket? later year Rx7?

Ideally, would like to keep the stock struts and work around that. Fabricating brackets etc is not an issue.

Appreciate suggestions as to how should we approach this upgrade?

Aaron Cake

iTrader: (1)

If you are serious, full FC front subframe swap. It's not really insanely involved but will take more than a weekend and a little fab work. Not only will you get the wonderful FC 4 piston brakes and larger rotors but you'll also get the rack and pinion steering.

betegh9

iTrader: (1)

Then why own an FB? All those costly, non safety changes would place the car above the $500.00 limit and you will be penalized laps. Bribing is a common exercise during BS inspection.

rotaryken

Fortunately, the LeMons rules allow for the braking system not be counted toward the $500 limit. We have the Mazda factory manual but it only covers the 1985 specs. Is there a site that might have the technical specs on the fc? If the discs are larger along with the calipers it would be neat if they could be retrofitted to our struts. Fabricating any necessary brackets are not an issue.

Aaron Cake

iTrader: (1)

There is no easy retrofit between the FC and FB brakes when using the FB subframe and spindles. Spindle diameter and length is different, brackets aren't really even close, FC uses a hub while the FB bearing rides in the rotor, etc.

The FC brakes are quite a bit larger. I forget the exact diameter but the increase is considerable and of course the FC calipers are 4 piston aluminum.

I did a quick search in the 1st gen forum for "fc subframe swap". Here are some links to get you started:
https://www.rx7club.com/1st-generati...-i-did-967834/
https://www.rx7club.com/1st-generati...ersion-960167/
https://www.rx7club.com/1st-generati...pinion-953514/

RXSpeed16

iTrader: (41)

Re-Speed offers conversion kits or at least gives you an idea where to start. It upgrades to the 2nd gen hubs, rotors and 4-piston calipers. They have had some issues lately regarding customer service, but I haven't heard many complaints from people that actually got their parts. So I'd suggest contacting them directly for part ETA's, etc.
Brake Conversion Kits

As for the lemons tech:
A) The inspectors don't care how much you upgraded your brakes on your FB.
B) You'll never be competing for a podium spot with a rotary engined rx7.

If you really want to go "by the book", print out the price of new fb braking system components. Compare that to the cost of the conversion kit. But they will be far more interested in how many blow-up dolls and live animals you can simultaneously fit in the car at the same time.

rotaryken

Awesome! Appreciate the help. The links are very helpful with tons of ideas. Thanks for getting us started on the right track.

As far as the competitiveness of the rotary in LeMons.... This is our challenge. Last month at Sears Point we are vey proud of our 8th place out of 174 cars with the 84th fastest lap. The fb can be made to handle and corner as well as any other car. We lose on straight line speed and braking. If we can get the braking system to be consistent for 15 hours we have solved part of our problem.

Let's face it, once you get hooked on the rotary and it's consistent torque over the rev range and its reliability... You become a believer. Of course Miatas and BMWs seem to have an edge but if we can tweak the braking and coax a few more HP then potentially we can improve.

There is so much great information available on the RX7 that we are trying to tap onto what's already been tried and not re-invent a wheel. This forum is incredible with knowledge and experience.

We just want to be pointed in the right direction. Whatever we learn we will be happy to pass on.

Again, really appreciate the comments.

Rotaryken

misterstyx69

iTrader: (142)

Until issues are Resolved with RE-SPEED(see Questions about Members Section) it is highly encouraged NOT to send any Members his way for business.
Thanks.STYX (MOD)

RXSpeed16

iTrader: (41)

Sorry, didn't realize it had gotten to that point.

xMUZZx

Thanks for the heads up. Ive been reading old threads and everyone was raving about them. Didnt know the business had changed hands. You saved me a headache i am sure.

rwatson5651

iTrader: (5)

Go to KC Racewares website and check out what he does, He makes lightweight brakes based on the GSL-SE design that will all bolt up to any large bearing spindle. Uses stock SE bearings and other parts and rotors from Coleman Racing. Very neat and VERY LIGHT. Call and talk to Charles, very knowledgable!!!!!

JimmyJackson

It will simply just demand a whole weekly work of yours i mean . . . the overhauling and one more thing there have been some issues later on . . just make sure to be screwing it right at the time of finishing . . . .