Can 322Mm Rear Discs Be Used On An R33 Gts25T ?

[discopotato03]

Hi all , I've found a larger front disc and caliper adapter conversion for my GTS25T and need to know if 322mm rear discs can be made to work and to avoid brake bias issues . The people with this front conversion used different pad materials to help the bias situation but I'd like to increase the rear brake size if possible .

I did search first but didn't find much .

Thanks in advance , cheers Adrian .

[Duncan]

Disc size itself is unlikely to cause an issue - which caliper are you thinking, how does the piston size relate to the original, and how much further out is the caliper than standard to fit a 322mm disc?

[blind_elk]

You also need to consider that the greater proportion of the braking effort is carried by the front brakes. Minimally larger rear brakes are unlikely to make a noticeable improvement to overall braking performance.

I have fitted GT-R rotors / calipers to the front of my R32 GTS4, and have not noticed any bias problems.

[discopotato03]

The caliper brackets are modified Z32 ones and moved out std R33 GTS25T calipers , I think std R33 rotors are 297 and GTR 320 so half of that .

I did actually drive the car that used them and while the brakes are very good the bias has changed because the front braking increased significantly with no change to the rear .

I just wanted to know if the rear 322mm rotors fit and would caliper extentions work .

A .

[djr81]

How wide is the rotor in question? Most rear rotors are markedly thinner than their front counterparts and do not cool anywhere near as well.

[_Wing_]

Assuming you have a standard R33 rear brake setup; 2 pot rears with 297mm rotors, by going to a 322mm rotor you'd be increasing the diameter by 25mm, which is 12.5mm in radius... in which case you'll have a hard time moving the standard lug-mount caliper by such a small amount. There's a few other issues that need to be addressed as well.

Having said that we have been doing lots of Nissan brake-related work at work, looking at better upgrades than the usual GTR brembo upgrade or the bigger rotor + caliper spacer upgrade but without spending toooo much money and managed to design something similar to what you're thinking but it's yet to be be put through a good workout.

[Legionnaire]

I guess it's a question about R34 GTR or 350Z rear brembo discs ? They are thicker that standard GTSt discs, 22mm vs. 18mm if i'm not mistaken, so something has to be done to pads in order to make rear sumitomos fit.

Other than that, the last time I checked, 322mm rotors for 350Z were disgustingly expensive and late GTR34 were nearly unobtainalbe (and expensive as well). Dunno, maybe this changed lately...

[discopotato03]

Old thread I know . I looked at R33 GTR spec brakes and they went to 300 x 22mm disks from the 25Ts 297 x 18 .

Also the rear Brembos had 40mm pistons compared to 38.18 on the GTS25T .

Slightly larger thicker discs and slightly larger pistons compared to the Rwd version .

A .

[GTSBoy]

Still a waste of time.