Four Piston Calipers

[discopotato03]

Hi all , just curious to know if piston sizes changed from R32/Z32 through to R34 GTR . Not after specs on Brembo or aftermarket calipers just the normal bits . I'm interested in what works and is cost effective on an R33 GTS25T . From a little searching the R34GTt fronts look straightforward except the bolt hole size . Provided the upright is removed and placed in a radial drill it should be simple depending on how tough the material is . Can someone tell me if the GTt calipers are aluminium because unsprung weight is important to me .

Also I don't know off hand what R33GTS25T's use on the back but suspect ventilated with internal drum park brake ? What is the usual upgrade from std ie R32/33 GTR ?

Thanks A .

[salad]

ventilated twin pot with 296x18mm rotors (not too sure about the thickness) with drum handbrake

all the gts-ts have the same rear brakes and non brembo gtr are the same. pretty sure...

[Ronin 09]

pretty sure the GTt caliper is aluminum.

the only cast iron calipers are the R32gtst 4 potters (I think).

the rear GTR brembo is an upgrade to the factory Sumitomos:

GTR32 (Sumitomo)

Front Caliper Piston (diam x qty) - 40.4 × 4

Rear Caliper Piston(diam x qty) - 38.18 × 2

GTR33/34 (Brembo)

Front Caliper Piston(diam x qty) - (44+38) × 2

Rear Caliper Piston(diam x qty) - 40 × 2

However, while the std GTR32/GTSt32/GTSt33 rear rotor is 296x18mm, the brembo is a 300x22mm for a little more heat capacity...

We (Roy) and i are trying to use a 350z rear rotor (322x22) with the brembo R33GTR rear caliper and offset bracket for a bit more balance running AP CP5555s 6pots with 355x36 fronts.

Hope that helps

[salad]

r32 gts-t calipers are alluminium aswell, the only ones that i know of that are cast are s14, s15 calipers

[discopotato03]

Thanks , be interested to see how the 350Z/GTR Brembo set up goes .

Cheers A .

[Roy]

Its a head feck but damned if its going to beat us

[discopotato03]

Just a thought Roy , is it worth considering using early Mazda RX7 four piston calipers on the rear . I thought they were aluminium and designed for either 20 or 22mm thick disks . I know the mounting ears are quite wide between centres but hydraulically speaking may suit your needs . Pads should be available is all sorts of compounds for them .

Cheers A .

[Ronin 09]

Was actually considered porsche rears - they have similar piston area to the std brembos (i.e not so different to justify a master cylinder change), and also most porsche master cylinders are around the same size as factory Nissan GTR.

having said that, not sure it is really necessary- the big twins in the brembos should be OK given that we don't have alot of weight in the rear.

porsches, from my understanding, work the rears alot more because of that lump of motor hanging out behind them.

also i reckon a twin piston also has less to go wrong!

cheers