roadster7

ok gang, i did a search but didn't really get the answer i need. everything i read while searching said the the 4-piston FC caliper and the 4-piston FD caliper are the same with the only difference being the way they look outside. now, can an FD caliper be bolted right up to an FC without any problems? that is the info i need.

i am in the middle of modifying a set of FC front spindles to be used on the front of a miata to convert the car to 5-lug. i will be running standard RX7 brakes with the setup, but i think the FD caliper looks nicer than the FC unit, so i would prefer to use the FD calipers if they bolt right up to a FC spindle and work properly with FC rotors.

can someone please help me out here.

thanks
alex

dclin

iTrader: (4)

The FD calipers not only looks nicer, but is also much lighter. The FD calipers are aluminum. Beyond doing the 5 lug conversion, I'm not sure how much more work is needed to adapt the FD calipers to the FC mounts, but I know it can be done. A past, local FD owner I knew was ripped off by a service shop many years ago; they replaced the calipers on his FD with those off of an FC. I still might have pics somewhere.

I would try posting in the 2nd gen section as well.

peejay

So are the FC calipers. At least, I've never taken a magnet to one, but they sure *corrode* like aluminum, instead of rusting.

hIGGI

iTrader: (7)

FD calipers use same brake pads like FC, but rotors are 296mm, while FC rotors only 276mm.

I would like to know if i could use both FD calipers and rotors on FC hub to get extra 20mm of diameter on front brakes. Even if it would mean some machining of brake rotors to fit properly.

Anybody tried or coudl try?

Turbo23

iTrader: (4)

I know some guys use FD big brake kits on their FC, they just make a adapter plate.

hIGGI

iTrader: (7)

anything could be adapted, of course.......but question is about 'bolt on swap'

Pat McGroin

There have been plenty of threads on this. The FD calipers have the same dimensions as the FC calipers, accept same brake pads.

Now the only thing I heard was getting some custom brake lines, but from the looks of it I think you might be able to get away with using 4 pot hardlines and maybe bend them a little.

But, the Fd calipers bolt on to FC 5 lug hubs. You cannot fit the FD rotors onto an FC hub because where the calipers bolt on are not properly spaced for the larger diameter FD rotors.

Edit- Hey roadster7 if you know another set of FD calipers for sale let me know, locally too.

uhh

So with a small adapter you can use the larger fd rotors on your fc calipers? Nice

Pat McGroin

You could, but would it be worth it for you??? Seeing as how many LS1 FC's use the stock 4 pots on the track with no problems as long as you have good pads and fluid.

uhh

^^^ if I was to need to buy new rotors anytime, could just make the adapter easily at my friends machine shop and throw the bigger rotors on. It would be for be the bigger rotor look only. I wont do it though, I dont care enough. Its just nice to learn little tid bits =)

Pat McGroin

What would be sweet is machining adapter plates for the porsche turbo calipers.

roadster7

i'm not looking to use both the FD calipers and rotors, just the calipers. so basically i can use the FD calipers in conjunction with the FC rotors right? see, here is the thing. i don't have a RX7, but rather a miata and i'm doing a 5-lug conversion on my car. the way this is done is with FC front spindles that are modified to have an upper ball joint mount, but this is getting off topic. so i need to run rx7 brakes with the setup as i don't really need anything larger than that, but i would rather use the FD front calipers than the FC ones, so i just wanted to make sure that they would bolt on to the FC spindle with no problem and work fine with the FC rotors with no problem.

thanks
alex

RETed

The FD calipers are of a special "squeeze cast" technique that got a few ounces shaved off them.
Otherwise they are identical.

Yes, you can run the calipers to run the FD rotor diamters.
The FD calipers are mounted differently due to the hubs.


-Ted

roadster7

RETed, either i am not understanding your post or you didn't understand mine. from what i have read so far, the FC and FD rotors are of different diameters, with the FD having a larger rotor, so you can't just use an FD rotor on an FC without a caliper spacer. now, since the FC and FD calipers are supposedly the same, will the FD caliper simply bolt directly onto an FC spindle? in doing so, could you just run the FC brake rotor and the FD caliper?

if anyone has done this, please let me know. also, if someone is running the FD caliper and FD rotor on their FC, can you help me with any possible adapter i might need to make.

thanks
alex

Pat McGroin

I didnt understand REteds post either but what you just said about FC rotor with FD caliper on an FC hub will work.

It's not the thickness of the FD rotor that's different(from what I have read) but the overall diameter of it.