*Z2 Brake upgrade - and issues...

[BlackSupra]

Well did the 'test fit' of the brake setup tonight. And here is what i found.

R33 caliper mounting bolt spacing is larger than that of the MZ21 factory calipers. But only just. (5-8mm by eye)

BA falcon rotors and the MX83 hubcentric ring will fit onto the MZ21 hub, however there is just one minor problem.... the rotor has compressed the dust guard onto the steering arm ball joint.

The rotor has slightly increased track, but only by a few mm.

Now the question is, do i cut away the dust guard and run with a waffer thin gap between the rotor and ball joint, or do i look at other alternatives such as the JZA80 disc.

For reference:

Dia height thickness centre hole
MA70 : 300 53.5 22 60

BA Falcon : 298 65 28 71.5

JZA80 : 323 50 30 62

Photo:

[takai]

Well the increase in track is normal. From what i know of the Cressida guys they simply either cut away the dust guard, or flatten it out so that it doesnt hit.

Interested to see how you get around the different bolt spacing, there is a Z20 here which wants a brake upgrade.

[BlackSupra]

Added photo.

[Dom-AE71]

Glenn if u want i can dig around for a Zoom mag i have with a tech article for a MZ21 brake upgrade. have you seen the issue im talking about?

[BlackSupra]

Yeah, JZA80 discs with the R33calipers.

Custom mount bracet and hubcentric ring.

[takai]

Ahhh, teh custom mount bracket.

[BlackSupra]

This is the same design as in zoom.

http://70supra.com/supra-diy/caliper/caliper-2.htm

[CrUZida]

Gimme a couple of weeks and I'll make them all love each other.

[takai]

Im not sure i want to know how you would make them love each other.
My initial thoughts woudl be to put a spacer on the underside of the BA disc like in the JZ conversion, and then appropriately space the caliper out with the adaptor plate. That will give you an extra bit to play with.

[BlackSupra]

haha will just have to run more camber to make up for the spacer

[takai]

Make love to your guards with a large cylindrical object...... like a guard flarer.

[1200det]

haha will just have to run more camber to make up for the spacer

Like me

[BlackSupra]

Ok, so here is the killer.

The back of the R33 caliper mount sits flush with the back of the bracket. Now this is a huge woohoo as you only need to run a bracket between the two!

HOWEVER, there is NO way to mount the caliper and utilise the full face of the disc!!!

I did the same thing in the conversion above, trimmed a bit of heatsheild and moved the caliper around.

The problem with this is the disc is too SMALL! This would work perfectly fine for the JZA80 disc and explains why you can't use the inside of the rotor... you cant get the caliper inboard any further!

So the options are: Buy the exisiting JZA80 kit or look at R33 GTST rotors and use pewee's hub ring.

[1200det]

Where can you get the JZA80 Kit ? I tried contacting the guy in ZOOM and he no longer works there nor has the mounting brackets and rings

[CrUZida]

R33/R32/Z32 caliper's do not work well on a disc greater than 300mm.

At 324/326mm you have to space the caliper out further (away form the centre) such that the top centre of the pad protrudes past the disc, thus not giving full pad coverage.

There is no way around this.

[BlackSupra]

Well i cant make it work with the BA Falcon rotor.

Was looking into Audi A8 (321mm) as an alternative, but if you say that i may need to look into alternative 300mm options

I need a hat height of around 63mm to clear the ball joint and maximise the space for the caliper behind the wheel and infront of the rotor. That is my main clearance problem.

By running a smaller hat height (<60mm) the nissan logo on the caliper will hit the back of the rim spokes.

I have dished front rims, so wont affect those people running the higher offsets.

[BlackSupra]

R33/R32/Z32 caliper's do not work well on a disc greater than 300mm.

At 324/326mm you have to space the caliper out further (away form the centre) such that the top centre of the pad protrudes past the disc, thus not giving full pad coverage.

There is no way around this.

Reading the ZOOM article and grant reported that the pads have full contact with the rotor. (on a JZA80 rotor 323x30)

The problem is the actual factory mounts are in the way of mounting the caliper and it's impossible to get the caliper any closer.

Thus you need the bigger disc to space out to where the actual caliper is.

Have you got any pics showing the GTR rotor and the caliper sitting over them, showing the pads?

[CrUZida]

Its not possible to have full pad coverage of R32 calipers and 300+mm disc (I'm assuming R33 is identical to R32 just with longer legs).

I ground a mm or so off the caliper and there was still caliper/disc interference.

You'd have to grind more than a mm off the caliper to get the clearance.

No pics yet.

[BlackSupra]

I dummied it up with cardboard and i see what you mean.

IF in fact the R33 has longer legs then this is causing me a drama, do you know or could you possibly measure an R32 caliper leg height for me?

[CrUZida]

8mm shorter legs