GT-R Brembo Brakes on r33 GTS-T: Rotor sizes and mounting brackets?

[IXMandalorianXI]

Hello all,

Me again with more brake questions, lol.

I have a r33 GTS-T. The calipers are GT-R Brembos, but the previous owner put oversized rotors on (14in/355mm front and 13.5in/343mm rear). I'm not sure where he sourced these rotors, but I have been unable to find replacements of the same size.

The EBC rotors I purchased designed to fit the r33 GT-R are 12.8in/324mm front and 11.8/300mm. They also sold GTS-T rotors which are 11.6in/296mm front and 11.5in/295mm rear.

I'm not really sure how to approach this. Right now. My Brembo calipers are too far away from center to use my purchased rotors. Can I remove the Brembo mounting bracket adapter and bolt the calipers directly onto OEM mount? Can I purchase new mounting bracket adapters to fit my smaller rotors? Or do I just need to source larger rotors?

I appreciate any advice.

Thank you.

Edited April 14, 2023 by IXMandalorianXI

[Murray_Calavera]

Hello again! 

Have you brought the rotors into a brake supply store in person? I would expect that the current rotors could be matched up pretty quickly if the staff at the store were able to play with them in person. 

[IXMandalorianXI]

Just now, Murray_Calavera said:

Hello again! 

Have you brought the rotors into a brake supply store in person? I would expect that the current rotors could be matched up pretty quickly if the staff at the store were able to play with them in person. 

I called EBC and they didnt think they had anything but they might have been trying to match the car, not the combination situation I have. I didn't think of trying to go in person. That might be the optimal solution.

[Murray_Calavera]

2 minutes ago, IXMandalorianXI said:

I called EBC and they didnt think they had anything but they might have been trying to match the car, not the combination situation I have. I didn't think of trying to go in person. That might be the optimal solution.

Once they match up the rotors for you, just make a note of what car they come standard on to make life easier in future.

[ACTIVE-LSD]

Yeah those rotor sizes are uncommon. I wonder if they were purchased from HFM Parts?? they are the only company that i know of that do irregular rotor sizes. They do R33 GTR 354mm front & 340mm rear.

 

 

[IXMandalorianXI]

Was on the phone with EBC and looks like the Nissan 370Z has 355mm fronts and 350mm rears. And is compatible with the r33.This MIGHT be it, and I'm going to re-measure my rears and see if this solves the problem.

[IXMandalorianXI]

2 minutes ago, ACTIVE-LSD said:

Yeah those rotor sizes are uncommon. I wonder if they were purchased from HFM Parts?? they are the only company that i know of that do irregular rotor sizes. They do R33 GTR 354mm front & 340mm rear.

 

 

Oh, thank you for the information. I will check that out.

[Dose Pipe Sutututu]

40 minutes ago, IXMandalorianXI said:

Was on the phone with EBC and looks like the Nissan 370Z has 355mm fronts and 350mm rears. And is compatible with the r33.This MIGHT be it, and I'm going to re-measure my rears and see if this solves the problem.

Take a photo, if you're using dogbone/adaptors it might give us a better understanding.

370Z calipers are actually Akebono.

[IXMandalorianXI]

3 minutes ago, Dose Pipe Sutututu said:

Take a photo, if you're using dogbone/adaptors it might give us a better understanding.

370Z calipers are actually Akebono.

Should have time tomorrow to lift her up and take photos of everything. Would different calipers require different discs? I know for certain I have Brembos on the r33 GTS-T.

[Dose Pipe Sutututu]

10 hours ago, IXMandalorianXI said:

Should have time tomorrow to lift her up and take photos of everything. Would different calipers require different discs? I know for certain I have Brembos on the r33 GTS-T.

Yes different calipers require different discs as the offset would be different.

Snap up a photo, I'm sure all of us can try work out what you have 

[Duncan]

Easiest way out is probably to ditch the adapters and bolt the brembos straight in the stock location, then use factory R33/R34 GTR discs. They will be sufficient for anything except serious track use

*edit* 

sorry let me clarify that. You need to know if you have R chassis brembos (what I assumed above) or Z chassis bremobs because they require different disc offsets. If your ones are Z chassis brembos your caliper adapter should just allow you to run standard size and offset z chassis discs. 

Bit hard to guess this on the internet. DBA.com.au have a very good catalogue which will allow you to measure and identify the discs you have.

[GTSBoy]

Yes, this all goes back to the first thread from this OP where I questioned the possibility that the calipers were indeed not R chassis GTR.

[IXMandalorianXI]

Ok, so several updates

I remeasured both the front and rear rotors:

• Front: 355mm x 32mm
• Rear 350mm x 20mm

Which reflects the 370Z exactly.

On 4/14/2023 at 1:36 PM, IXMandalorianXI said:

Was on the phone with EBC and looks like the Nissan 370Z has 355mm fronts and 350mm rears. And is compatible with the r33.This MIGHT be it, and I'm going to re-measure my rears and see if this solves the problem.

Next, as requested, pictures:

FRONT BRAKES:

REAR BRAKES:

[Dose Pipe Sutututu]

3 hours ago, IXMandalorianXI said:

Which reflects the 370Z exactly

Make sure you measure the hat height/offset too.

Looks like someone has manufactured dog bones to suit, haven't seen such kit before! 

[Duncan]

OK, so the answer to your original question, you need to sell or return what you bought, and buy 370z discs and pads.

[IXMandalorianXI]

So, some exciting updates.

1.) EBC has been super helpful and is exchanging my rotors for properly sized ones

2.) On the way to work today, my brakes seized up and would not to fully unclamp from my rotors, causing them to become red hot.

3.) I took it to my mechanic and he thinks my ABS might have gone bad, among a number of other things. So I decide to nuke this problem and am having him completely rebuild my brakes with a new master cylinder, ABS block and caliper pistons. And just because I'm officially sick of dealing with these brakes, I'm going to have him put the new rotors and pads and and bleed it the damn thing for me, lol. For the price he offered and the quality of work he does, I can't complain.

I really appreciate everyone's information and help, thank you. I learned a lot through this little adventure!

Edited April 17, 2023 by IXMandalorianXI