R32 Brake Problems After Swapping To Gtr Brakes

[Unclerico]

So I have a daily driven 89 Skyline GTE (no ABS) that I swapped to 5 lug hubs and R32 GTR brakes. Im using freshly turned OEM rotors, new Hawk ceramic pads and steel braid lines. At first I just used the stock GTE booster and master cylinder. After I fully bled the system and took it out to bed the brakes I could tell before I even got out of the garage that something was not right. The pedal pressure was stiffer than it should be and the car was just not slowing as much as it should. So I went out and bed the brakes anyway hoping that it would "come to life" if I just drove it a while. After about a month of driving the car this way I noticed that the rear rotors looked like they were still brand new. I could clearly see the cross hatching from being turned, its as if the rear pads are not clamping onto the rear rotor. When I step on the pedal the car just does not slow like it should be, my stock GTE brakes felt way better than these GTR brakes.

So I thought maybe the master cylinder is bad? So I bought a brand new bigger 1" master, swapped it out and bled the entire system again. I got the EXACT SAME FEEL!!! Stiff pedal and the car just does not stop the way it should. If there is an emergency situation where I would need to slam on my brakes they will just not be there for me.

Im totally lost on what it could be and I would really love some useful information and not your typical response of "bleed your brakes again".

Ive been a race mechanic/fabricator for the past 15 years and know how to bleed a cars brake system. Ive tried every different sequence that Ive found online. Ive tried using a pneumatic bleeder and hand bleeding, nothing seems to change the stiff pedal and weak braking power.

Please help.

[GTSBoy]

Enlighten those of us who have no idea what sort of car a GTE is. What brakes were on it? The same little sliding calipers as on all the other NAs? Do you happen to know the piston diameters of old and new?

[Robocop2310]

Please clarify - when you say R32 GTR brakes you mean the stock Nissan ones or the Brembo variants? Also, What is a GTE - you mean GTS?

Cheers

[admS15]

GTE electric hybrid skyline? Lol

[Ben C34]

Do the pistons move in the rear calipers? Pull them off the disc and get a friend (or pay someone) to push the pedal and see what happens.

It's not rocket surgery

[Ben C34]

GTE Coupe and Sedan 2.0 L RB20E I6, 125 PS (92 kW; 123 hp), 152 N m

[Ben C34]

Does it even need brakes? /;)

[Robocop2310]

Sounds to me rear breaks weren't installed correctly. Eg. the pistons not connected or brake pads not installed properly.

[hardsteppa]

After about a month of driving the car this way

Ive been a race mechanic/fabricator for the past 15 years and know how to bleed a cars brake system. Ive tried every different sequence that Ive found online.

wait, you had crap brakes that you yourself say won't work in an emergency situation and you've driven it around this way for a month? give a fk for the safety of other road users much??? I really hope I've misunderstood what you posted.

And I would suggest, look elsewhere rather than bleeding the brake system again. Stuck rear calipers as Ben said, or check booster is working properly.

[blind_elk]

First up, the rear brakes do next to no retarding of speed. The majority of the stopping is done by the front brakes.

To the main problem at hand - are these calipers brand new or second hand? If second hand, did you put a kit through them, and ensure that the pistons actually slide in the caliper body?

[Unclerico]

So yes it is a GTE and it is just a base model Skyline with the same sliding brakes as all the other base model NA vehicles. The R32 GTR brakes that I installed are the standard GTR non Brembo brakes.

The brakes that I installed were a used set that came directly off of another perfectly running GTR that actually did stop when stepping on the pedal. So no the pistons are not seized or anything funny going on like that.

And ok I may have over exaggerated a tad when I said I couldnt stop in an emergency. Was simply just trying to get my point across. Dont beat me down. lol

As for the booster, yes it very well could be the issue. Im not saying it isnt but the stock brakes with the same booster and master worked perfectly fine just hours earlier before I did the swap. So that would just make me think it is not a brake boster issue. However I think Im going to change it out anyway just to check.

I do realize that the rear brakes do not slow the car anywhere near the way the fronts do. I know this is sort of a "safety system", if you will, from the factory so people dont lock up the rear brakes first and spin out. However after 2 months of driving on fresh rotors it should not still have cross hatches from being turned. Those cross hatches should be gone within a day or two.

I doubt there is but its almost as if there is some kind of restrictor going to my rear brakes somewhere.

And since my pedal is so stiff its almost telling me to go back to a smaler master. I only went bigger in the first place because I figured I should at least start with the size that these calipers came with.

I bought a BM-50 for the Nissan Pathfinder. As it is the 3 port 1" master that works for RHD cars and I think its the only BMC that is readily available in the states. I read that this master is a "step bore master". For one I dont know if its true and if it is true would that cause this issue that Im having?

[GTSBoy]

It would be funny if the front and rear connection ports on the BM50 and your original shitter's master were opposite.....

[KiwiRS4T]

Have you checked to see if the rear brakes work at all - jack the rear wheels off the ground and stand on the brake pedal (from a fairly slow speed to start with)? Is your booster working at all (brake pedal feels different with engine on or off)?

I fitted a BM57 from an R34 GTR with the stock booster and pedal was not too hard.

[niZmO_Man]

Funny I had the exact problem when I swapped my stocker BM50 for a HFM BM57. No fluid going out of the rear calipers (I "bench bled" the new master and it pushed fluid out all ports). So yeah, check your master.

[GTRNate]

So yes it is a GTE and it is just a base model Skyline with the same sliding brakes as all the other base model NA vehicles. The R32 GTR brakes that I installed are the standard GTR non Brembo brakes.

The brakes that I installed were a used set that came directly off of another perfectly running GTR that actually did stop when stepping on the pedal. So no the pistons are not seized or anything funny going on like that.

And ok I may have over exaggerated a tad when I said I couldnt stop in an emergency. Was simply just trying to get my point across. Dont beat me down. lol

As for the booster, yes it very well could be the issue. Im not saying it isnt but the stock brakes with the same booster and master worked perfectly fine just hours earlier before I did the swap. So that would just make me think it is not a brake boster issue. However I think Im going to change it out anyway just to check.

I do realize that the rear brakes do not slow the car anywhere near the way the fronts do. I know this is sort of a "safety system", if you will, from the factory so people dont lock up the rear brakes first and spin out. However after 2 months of driving on fresh rotors it should not still have cross hatches from being turned. Those cross hatches should be gone within a day or two.

I doubt there is but its almost as if there is some kind of restrictor going to my rear brakes somewhere.

And since my pedal is so stiff its almost telling me to go back to a smaler master. I only went bigger in the first place because I figured I should at least start with the size that these calipers came with.

I bought a BM-50 for the Nissan Pathfinder. As it is the 3 port 1" master that works for RHD cars and I think its the only BMC that is readily available in the states. I read that this master is a "step bore master". For one I dont know if its true and if it is true would that cause this issue that Im having?

Please tell me you have the Part Number for that "BM-50 for the Nissan Pathfinder. As it is the 3 port 1" master that works for RHD cars" brake master cylinder! or at very least the exact year and model/trim pathfinder its from ! I am in Canada trying to find a replacement bmc for my R32 GTR!