eyeoutthere

I just bought an 86 “true base” RX7 (no sunroof, no power steering, no power windows, no rear wiper, no rear wing, etc...)

I would like to put 4-pot front, and vented rear disk brakes on it but I want to keep the nice 16” aftermarket 4-lug rims that it currently has.

Is this possible?

From what I have read, I would have to drill 5-lug rotors to a 4-lug pattern or find some 4-lug rotors that will fit. But, otherwise it would work.

So, what do you think?

Also, will a Turbo II rear end swap into a 4-lug car (as far as the half shafts fitting)?

Thanks,
Jason

eyeoutthere

anyone?

$150FC

you can swap the tii rear end with halfshafts onto 4 lug hubs, but i think the best way to get better brakes and keep the wheels would just be to get some badass rotors and pads.

eyeoutthere

I thought about that. But when the car is done, I will be autocrossing it and making ~300hp (I'm not just saying that).

Thus I want to do whatever I can to resist brake fade (which means vented rear disks and bigger front disks).

I have a 5-lug parts car already, but I just want the brakes.

Aaron Cake

iTrader: (1)

Not sure how you're going to make 300 HP NA in a form good for autocrossing, but anyway...

You can have a machine shop custom make a caliper bracket as long as they will fit under your aftermarket wheels. And yes, it should be pretty easy to redrill the 5 lung rotors. But by the time you have done all that, you might as well have just done the 5 lug swap...

eyeoutthere

I never said it was going to be a good autocross car. (I never said NA either)

So the 4pot calipers will not mount to the 4lug spindles? I thought only the hubs and calipers where different.

Please excuse my ignorance on the suspension setup of the FC. I come from F-body land where font suspension is terminated by upper control arms, LSD is called posi, and coolant flows backwards through the engine (oh, and I almost forgot about the whole piston thing).

mazdized

I have a 89 GTU and I have bolted on 4 pot calipers no problem. But honestly all you need are some Hawk black or blues and it will have more stoping power than your tires can handle.

Aaron Cake

iTrader: (1)

If you use the 4 pot caliper bracket, it should bolt up fine. If you use the single piston bracket, and adapter will be required.

eyeoutthere

Are the rotors the same size?

Dak

I believe an 89GTU is a five lug car.It just had single piston calipers instead of the four piston ones.Front rotors were the same in all five lug cars.

Icemark

Not even close to the same size. 4 piston front rotors are over an inch bigger, and the matching rear rotors are about 1/2 inch bigger (and considerably thicker).

Icemark

No, the 89 GTU had 9.8" front single piston, and 10.3 rears, while all the other 89 models had the 10.9" rotors with the 4 piston brakes and the 10.7" vented rears.

bingoboy

thats funny...because on my 89 GTU i did a swap from Single piston to 4 piston T2 calipers...and the rotors were the same size. i tookem off and compared them and all to make sure and then i left the original rotors on (ones that had been on with the singles). oh, and the rotors that were on with the singles were 10.9" diameter.

adamlewis

Youre not really gonna get brake fade on an Auto-X course...

Icemark

someone probably used the S4 heavy duty rotors, but I would surprised that they would fit without some major work.

eyeoutthere

That’s true, but I hope to one day graduate to a road-courses

Besides, those solid rear disk scare me

adamlewis

Well in that case I can see where youre coming from

jon88se

did i mis-understand aaron? the 4 pots will fit on a 4 lug car if you use the caliper bracket from the original 4 pot setup? please clarify, if this is true I'm placing an order w/ my OEM supplier hehe

Dak

Mazdatrix has the same front rotors listed for all five lug cars.For rears they have five lug vented(probably the 10.9")and non-vented(probably the 10.3")so I think you're right about the rears.I'm going by Mazdatrix on the front as I have never owned a single piston car.