R31/r32 Brake Upgrade......help!

[NismoR31Jet]

Heyyas.

On my R31 tha tI use for track days, I am currently running R32 GTR or R33 GTS-t sumitomo calipers (I cant remember what they are off) and 280mm DBA slotted disks with RaceBred custom pads (Racebred build GTP and targa porches and these are the targa compound). Rears are standard R31 brakes with drilled rotors and same pads as front.

This setup was fine with the RB30 making just under 200 rwkw but with the Rb26 making just under 270rwkw they are not cutting the mustard!

After 3 laps at sandown I get shocking brake shudder and the brakes are starting to fade badly

Now, I am looking at upgrading my brakes, but to what.

I had my mind set on Brembos from a 33 GTR but after looking around on here they lont look much larger than the sumitomos I am currently running. I am sure they are larger, but they are still a 4 pot and for the price, I am sure there is a better option.

I have noticed kits that use a dogbone bracket to mount the sumitomo caliper out further from the disk and run a larger disk (325mm I think?) This kit with alloy hats and disks costs around the same as a set of second hand front brembo calipers on their own!

But are the sumitomo calipers junk or are they ok?

I will upgrade the rears but with the matching caliper to what I use (or will be using) on the front.

Any info or opinions would be great.

[Roy]

If you are running 280mm rotors then they are R32 GTSt or Z32 calipers.

Depends on your budget, but at 3k i would be very tempted to use the AP 4 pot caliper with DBS 5000 324mm rotors that UAS sells. Race Brakes in Melbourne does a similar kit with the same caliper but their own 330mm rotor for another $400 odd.

OUt of interest, what times, tyres etc are you running at Sandown?

[NismoR31Jet]

I only managed 3 laps at sandown (kept loosing oil pressure above 6500 rpm) and the best I got was 1:30.

That was my first time out at sandown that was not in the rain!

At calder with the RB30 I managed a 1:10 with this brake setup.

I am not sure on budget yet, I guess I want to find out what I need and do my research and see what is out there.

Then I guess budget will be worked out then.

[Roy]

I only managed 3 laps at sandown (kept loosing oil pressure above 6500 rpm) and the best I got was 1:30.

That was my first time out at sandown that was not in the rain!

At calder with the RB30 I managed a 1:10 with this brake setup.

I am not sure on budget yet, I guess I want to find out what I need and do my research and see what is out there.

Then I guess budget will be worked out then.

What tyres? And what weight is the car?

The 324mm brackets are a decent upgrade for the calipers you have...but they are a band aid and whilst a good budget updgrade, if you have the money to spend then there are better options...starting with the CSC 343mm kit which is about $2800 including pads.

I would also grab some Z32/R32 rear calipers and rotors as well.

[NismoR31Jet]

this was using my regular street tyres.

Front are goodyear revspec 215/40 18 and rear bridgestone potenzas 235/40 18.

I was runnng some 15"s with semi comps, but I was getting more wheelspin with them as they are a bit small (only 205/60 r15).

As for car weight, a stock R31 in my model is around 1300 kg, mine has the rb26 now but has had the AC removed and the power steer removed so I would estimate around the 1300 should still be right?

I guess the first thing I should have done is run ducting to the brakes! I am sure the extra airflow would

have helped!

The only other drama is getting them to fit on an R31! I have had the face of the sumitomo calipers shaved off to give more clearance between the caliper and rim.

[Duncan]

I had my mind set on Brembos from a 33 GTR but after looking around on here they lont look much larger than the sumitomos I am currently running. I am sure they are larger, but they are still a 4 pot and for the price, I am sure there is a better option.

I totally agree....the gtr brembos are a popular upgrade but very bad value I think. Have a look at recent threads in here there are some good options including the just jap 8 spots for 2200.

[NismoR31Jet]

I think the biggest drama would have to be the disks.

They are either too small in diamater, or the DBA gear is not great quality which is contributing to the disks warping fairly quickly. Or even a mix of both.

which is why I am considering moving my existing caliper out and using a larger diamater disk. Yes, I know that the actual pad area is no greater, but there is more heat dissipation available with the larger disk?

[slip]

when i put the big brakes on my 31, the std DBA slotted rotors lasted a couple of months, and then upgraded to 4000series. And that was for mountain work, so it's not just you. At that diameter, youd need at least 4000series DBA, but i really think you need bigger diameter 4000series minimum. I'd go with that idea, dogbone it, same calliper, bigger and better disk, see what happens.

have you figured out the rear handbrake setup with 32 callipers on there? let me know if you need help.

[blind_elk]

Remove the backing plate behind the rotor, and fit some cool air ducting.

Fit braided brake lines if you haven't already.

[NismoR31Jet]

There are no backing plates on the front brakes from factory, but there are on the rears, I had removed them but didn't make much difference, but I really think ducting to the front brakes will make a huge difference.

As for rotors, I have noticed a few people on here having issues with the DBA rotors cracking, but what other disk manufacturers are there that do replacement slotted rotors? Are the RDA rotors any better?

As for the handbrake with R32 rear brakes.....How did you do it?

[slip]

commodore drum handbrake custom'ed on, with of course everything else custom. but they are CRAP. i really think there must be a better handbrake drum setup that could be easily adapted off another borg warner car. hsv rotors, which were not cheap, but slotted/vented, didnt want solid.

[NismoR31Jet]

commodore drum handbrake custom'ed on, with of course everything else custom. but they are CRAP. i really think there must be a better handbrake drum setup that could be easily adapted off another borg warner car. hsv rotors, which were not cheap, but slotted/vented, didnt want solid.

I am thinking using the backing plate and hand brake setup from an s13 or r32/33. That way I know it will fit the inside of the disk correctly.

I was thinking of doing the Commodore setup, and I have even seen XD-XE V8 fairlane rear brakes adapted, they use a 280-290mm (I think) vented rotor with a large caliper with the hand brake built in to the caliper much like an R31.

[slip]

that might be even better if you're not worried about handbrake strength. i was keen to do a bit of drifting and the commo handbrakes would have been useless. if you can get the s13/33 gear on there, let us know, that'd be sweet.