R32: Gtst Budget Brake Upgrade

[MarkE]

Ive bought some HR31 struts with the larger master cylinder etc., a set of R34 GT-T Sumitomo calipers, and yesterday received my blank DBA 324x30mm slotted rotors. Once I find somewhere to drill them in 114.3x4, and get a bracket made up to mount it all, should work a treat.

[Richard Everett]

Hi Roy,

Did anything come of the offset brackets?

Cheers,

Richard

[Roy]

Well, i was grabbing a few sets of calipers and was going to do 2 or 3 sets with new rotors. But after 3 years of running this brake setup, i just ran into a bit of a hitch which means i wouldnt recommend others do this upgrade:(

When running Rb74s brake pads the setup worked fine, and has for years. With the std 280mm rotors and RB74s i use to pull into the pits at Eastern Creek with smoke pouring off the brakes. With the 324mm rotors the brakes ran that much cooler and consistant, it was good upgrade.

So fast forward to just before Xmas and i changed to Comp 9 pads, which along with being a different compound is a fair bit harder pad material. As you can see on thepics on the previous page, the pads overhang over the edge of the rotor by about 1.5-2mm. Now it turns out i should have been more mindful of where the centre of the pistons located on the rotor, more then the pad face.

Basically the pistons sit a tad too far out on the rotor, so when the harder comp 9s weared down a little, the pistons dont actually force the pad square against the rotor, instead only really using about 50% of the pad face:( With the softer RB74s the pad was soft enought that it distorted and weared the whoel pad face. The Comp 9s being that bit harder dont do the same:(

So essentially this upgrade is dramaticlly better then std, but in light of what i have just noticed, it is still short of being 100% correct:( As such id recommend that others not do it, as it appears that if you want to run a racier pad then the setup will give you a spongy pedal when the pad wears a little, as the pad want to rock over the edge of the rotor and you get pad knock off:(

So will live with the spongy pedal for a few weeks, and ill start looking around at soem new calipers that can better suit the 324mm rotor.

[Roy]

But first things first, ill have a look at soem R32 GTR/R33 GTST calipers to see if they swallow the 324mm rotor, if not i may just go for some new AP 4 pots.

[Richard Everett]

Hi Roy,

The Sumitomo 4 pots off a R33 or R34 Gtst should do the job with the big diameter 324 mm x 30 mm discs.

This is what my son has about to be fitted up to his R31.

Only the caliper brackets to come ....... hence the interest in what you are doing with them!

Cheers,

Richard

[Roy]

Thing is the R32 GTST caliper and the R33 GTST caliper brackets will not be the same.

R32 GTST 280mm and 4 pot caliper

R32 GTR/R33 GTST 296mm and 4 pot caliper.

The 296mm brake setup bolts straight onto the R32 GTST which tells me the caliper is spaced differently to the R32 GTST caliper. So would not be able to use the same bracket anyway.

Im selling my car now, so will look and hope that the R33/34 caliper does the job better, otherwise ill sell the rotors and throw some cheap std rotors back on:(

The fact that R34 GTT rotors are 310mm i think i have a winner:)

[Trust33]

So roy,iyo are the r34gt-t callipers close enuf to straight fit,requireing little or no modifycation for an r33 gts-t?Reason being If they are a cheap straight swap then 1 would think that when going to upgrade to say slotted rotors that the gt-t styles would be the choice to make.

Or are the callipers on the 33 able to handle much bigger rotors than your 32?

[Roy]

Id rather not say until i get a set to try with my 324mm rotors. The ppl that did my brake upgrade should have known better. It still works great, but for the sake of a little more fiddling it should be able to work 100% and offer even better performance and pad wear:)

Either way if you are planning on running bigger rotors on your GTST (even R33/34) you will have to space the caliper to suit

[Rowdyr32]

Worth the upgrade. With stock pads and some used r33 gtr rotors the car now pulls up heaps better. No brake fade around phillip island. Cheap at $100 for the conversion making my own brackets.

[Richard Everett]

Hi Rowdyr32,

Interested in your posting.

Are you interested in fabricating a pair of offset caliper mounting brackets for my 324 mm discs onto my R31?

If so, please email me at [email protected]

Cheers,

Richard

[Roy]

LOL...Rowdy doesnt use the brake...he just tosses the car sideways 50mtrs before the corner and screams through sideways:)

Your results seem to reflect my experience over the years with this setup. It just appears when i have gone to a harder pad, halfway thru the pad depth im now getting pad knock off because of the caliper/piston offset on the rotor:(

Good to hear that someone else has had good results,

[B0oStEr]

Roy Could material be removed from inside the r32 caliper so it would fit over the 324mm rotor further?

Has anyone tried to fit the R34 GTT brakes to the R32 GTSt?

[Roy]

I would strongly recommend against machining the caliper. Some of the things you want from a caliper is low distortion/high rigidity. Machining it will only further weaken it:(

I was looking at an R34 GTT caliper the other day and think it will get the job done. Just have to be sure its the same as R32 GTR, R33 GTS25T.

Wont get a chance to try this before May when im talikg leave withou pay from work, if car gets sold before then i may not find out unless i buy another R32 in a year or two

[muaythailuke]

Do you know how much new pistons would cost if they are required?

$90 each from Nissan I was quoted and 2-3 week wait but they are just 38mm piston so you should be able to match it to somthing else with would be a bit cheaper, RX7 have a 38mm piston, volvo do to I think umm some others do too if you take it to a spare parts place that does a bit with brakes and should be able to match it up with something.

I recently bought some DBA4000 slotted rotors for my R33 GTS from Repco cost me $340-360 for the pair a plus a free set of standard pads which will do for the street and just change to a decent set of pads when I go to the track.

[B0oStEr]

8 x $90 = Hmmm, Wonder what they'd want for a pair of complete calipers.

I think I'll get a good second hand set.

BTW What is the pad no. for the R33GTSt? Is it the same as the R32?

[muaythailuke]

8 x $90 =     Hmmm,   Wonder what they'd want for a pair of complete calipers.

I think I'll get a good second hand set.

BTW What is the pad no. for the R33GTSt?  Is it the same as the R32?

Id hate to imagine what they'd want for complete caliper, I bought a pair of second hand rear calipers from the toy shop for $190 which I thought was reasonable.

Dont think the R32 and R33 would be the same, so I will find part no for you

[Roy]

And i suppose i shoud update this thread.

If you look at the rear caliper offsets from the factory on the R32 GTST then you will see they are exactly the same as my upgraded fronts, and result in the same wear.

Any probs i have had of late were traced back to maintenance, the fact that the slots are not to...hang on just read this thread:)...

http://www.skylinesaustralia.com/forums/sh...88&page=1&pp=25

If anyone wants, PM me your number...its easier to discuss over the phone:)

Basically its a good brake upgrade, witha simpe pad mod it wont even have any real adverse pad wear using the R32 GTST caliper, but with the R34 GTT caliper the upgrade will be that little bit nicer again:)

[Roy]

And if someone want to try this on their R32, well im selling the setup, have some bad ass calipers in the wings:)

Im selling because if i get rid of them now that they are freshly machined and with the pad i now use, i could probably only get another 7-8 track days out of them. With a set of RB74s they would no diubt serve someone else for another couple of years.

So figure while they still have a few years of good street service its time to get rid of them while they are still worht a few dollars.

[B0oStEr]

So can anyone confirm whether the GTT calipers and rotors are a straight swap for the R32?

[Roy]

The R33 calipers and rotors are a straight swap, im willing to bet the R34 are as well, though the rotors are 310mm rather then 296...only one way to find out:)