Question for RZ owners/knowledgable persons

[TonyC]

Hello all, I undersstand the RZ has larger brake rotors, but apparently uses the same 4 pot callipers as other RX7 models?
Is this correct?
If they use the same callipers does anyone know if they run a differnt hub to allow the calliper to be mounted (as the lugs will be further out if using a larger disk), or do they use a machined spacer?

Also, can anyone confirm the disc size on the RZ.

Thanks.

[Adie Moore]

cant help with reguards sizes and fitment but my rs also has bigger discs, so mayby guys with one of thesr could help out too.
adie

[clive]

Hi Tony,

The RZ uses a bigger one piece disc that you only find available from Mazda at £200 plus vat per disc and also it uses as far as I know the same caliper with a different mounting bracket to relocate the caliper further out.

[monkey-fd3s]

I think you have to use a caliper spacer kit.  The billetbitz dude made one I think or you could have your own machined.

[TonyC]

Cheers, I\'m not really after the disk but I\'m inerested in how they mounted the same calliper to the same hub - if the disk is only slightly larger there is a nasty overlap on the lugs which would make a spacer difficult to make up.

Has anyone any pictures of the callipe/hub mounting.
In fact, Clive, do you have the spacer listed as a part or does it appear in the RX7 parts catalogue?
Interestingly, I\'ve been chatting to Rixio and he doesn\'t think the discs are larger. Maybe the only way to get an answer would be take him up on his kind offer to pop over and have a look - I can take my disc with me to check!

I\'m all set to make up my own bells/rotors and have a friend who can machine up a spacer - but I didn\'t like the look of the lug overlap.

[clive]

It\'s not a spacer it\'s a totally different caliper mount casting,

[TonyC]

Chees, thought it might be based on the hub.
I have found that the RS did have a bigger disc. And thicker. Which means it surely must have had a different calliper as well.

IE: the normal, early FD like mine has a 294mm disk, and the calliper will not accept a disk thicker than about 24mm -in fact the standard disc thickness is around 22mm.
The RS apparently has a disk 314mm in diameter, but 32mm thick. So they must either have a different calliper or the same calliper but with a space in the calliper. In fact it must be a different calliper as the piston diameters are different it seems.

[Mazdarotaryparts]

Hi Tony and all,

We have still to work out a final price but soon MRP will be selling a big rear brake kit with a relocating bracket for the FD so you still use the O.E. rear calliper,

The drilled and slotted 2 piece Disc will be 322x20mm (12.7" x 0.8")

A front standard diamiter 294mm 2 piece drilled and slotted disc will also be made avaliable to match the rear but this is a little thicker than stock at 24mm instead of 20mm but most pads will still fit straight in.

[TonyC]

Interesting Clive, how did that project come about? It is unusual to increase the rear disc over the fronts (although my Mg Zt V8 actuall had larger rear brakes than the front-braking was very very good on that car).
A little tweek on the rear brake bias and that could be very interesting indeed. In a good way!
That and a thicker front disc (which again helps heat disapation) might work well on the track....
have you had the kit running on any cars yet?

[efiniste]

Is that the Racing Brake kit Clive?

[Mazdarotaryparts]

Yes - MRP are an offical Racing Brake dealer.

This is the kit that people had long been waiting for. Will have this on our on-line shop soon. Watch this space!

[efiniste]

Are you planning on stocking the front kit with the new (Racing Brake) caliper?

[Mazdarotaryparts]

Hi Tony and all,

I do know that RB tested this product for a long time before recently releasing it for sale, most of their stuff seems to be test through use in SCCA.

We have wanted an easy to install larger rear brake set up for a long time for two reasons, we know the FD really needs a bit more brake on the back on track and for years have been supplying soft Hawk pads to give a little more bite.

The other reason is when you see our guys with 18" and 19" wheels on their "show" cars the stock disc\'s look silly, this conversion will fill their big wheels very nicely :cool

We will be importing initially 1 full set to give us the true cost of this kit to us and from that we will work out a "retail" price for the U/K market.

Here\'s a picture of the front Disc, also we have tested these Disc\'s on track over here at Brands with our own choice of pad and been very pleased against the same pad set up with stock disc\'s on the same car

[JohnnyP]

Tony, I asked a similar question recently on disc sizes.

Have a look here http://www.mazdarotaryclub.com/forums/showthread.php?t=39606

[Rixio]

Hmmm seems i was wrong Sorry T :o

Visually i cant see much of a difference...may have to compare off the car to actually be able to notice it...

So quick question...would it make any difference running stock sized disks on a Rz?

Rixio :Thumbs-up