S15 brakes
corresponds with other info on web, but then again they might have used the same source, however, think it is correct as some bmc are marked with both BM# and size.
BM44 = 15/16 = 23.8
BM50 = 1" = 25.4
BM57 = 1 1/16 = 26.9
and from this:
Brake Rotor / Caliper information
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R32 GTST
Master Cylinder diam (mm) - 25.4 area 506.71mm^2Front Caliper Piston(diam x qty) - 40.4 ×4 = 5127.58mm^2
Front rotors (diam x thk) - 280×30
Rear Caliper Piston(diam x qty) - 38.18×2 = 2289.78mm^2 ratio FR = 2.239
Rear Rotors (diam x thk) - 297×18
total 7417.36 brake to master ratio 14.63
R33 GTST
Master Cylinder diam (mm) - 23.8 444.88mm^2Front Caliper Piston(diam x qty) - 40.4 ×4 = 5127.58mm^2
Front rotors (diam x thk) - 296×30
Rear Caliper Piston(diam x qty) - 38.18×2 = 2289.78mm^2 ratio FR = 2.239
Rear Rotors (diam x thk) - 297×18
Total area 7417.36mm^2 brake to master ratio 16.67
R32 GTR (Non V-Spec,)
Master Cylinder diam (mm) - 25.4
Front Caliper Piston(diam x qty) - 40.4 ×4
Front rotors (diam x thk) - 296×32
Rear Caliper Piston(diam x qty) - 38.18×2
Rear Rotors (diam x thk) - 297×18
R32 GTR V-Spec / R33 / 34 GTR with Brembos
Master Cylinder diam (mm) - 26.9 568.32mm^2Front Caliper Piston(diam x qty) - (44+3Cool×2 ... leading pistons smaller then trailing 5309.29mm^2
Front rotors (diam x thk) - 324×30
Rear Caliper Piston(diam x qty) - 40×2 2513.27mm^2 ratio FR = 2.1125
Rear Rotors (diam x thk) - 300×22
total 7822.56 brake to master ratio 13.76
This is the ratio of master piston movement to overall brake pad movement
R32/GTR calliper ratio 15.43
R33/GTR calliper ratio 17.58
So there isn’t much difference between the Brembos and the std Nissan R32/33 GTST calipers and R32 GTR callipers
Oh...and an old favourite that seems to be a good practical test of what the theory suggests....
Car & Driver did a test a few years ago ...Test Car was a WRX (US Spec which only uses two piston sliding caliper, not as good as Nissan 4 spot or later Model WRX 4 pots)
So tested kits were, std car, std car with upgraded pads and fluid, Brembo F50 Kit, Brembo Lotus Kit (Similar to as fitted to GTRs, 44/38mm pistons), Stoptech it and Prodrive Kit (Alcon)
Stopping Distances 70mph - 0 , 3 Stop
Brembo F50;_____________ 185 / 183 (Average / Best)
Brembo Lotus; ______________ 200 / 196
Prodrive; __________________ 198 / 194
StopTech;__________________ 187 / 186
Stock; ____________________ 205 / 196
Stck with pads and fluid; ____187 / 184
The above figures are all in feet, one stop difference between pad and fluid upgrade to crappy sliding caliper brake setup and massive Brembos is 1 ft...lol 30cms And over 3 stops the average is 2 ft...lol 60cms
So you can see the one stop max of the upgraded pads and fluid is damn good when you consider the $$$ to % difference.
Stopping Distances 100mph - 0 , 25 Stop
Brembo F50; _____________ 299 / 288 (Average / Best)
Brembo Lotus; ______________305 / 294
Prodrive; __________________ 308 / 295
StopTech;__________________ 297 / 290
Stock;_____________________ 340/317
Stck with pads and fluid;_____316/299
Not the world of difference you would be led to believe by the "you need 6pot caliper 343mm rotor crowd."
Specs of the kits:
Rotor Weight (pounds) Size in inches (diam / thk)
Brembo F50;.................15.8......................... .13.1 / 1.3
Brembo Lotus;..............12.9.......................... 12.9 / 1.1
Prodrive;......................16.5............... ............13.0 / 1.1
StopTech;...................13.9.................. ........12.9 / 1.1
Stock;.................. ......14.2..........................11.6 / 0.9
Caliper Weight , Piston Size, (mm)
Brembo F50;..........8.6 pounds...........40 / 44, Leading / Trailing
Brembo Lotus;.......6.8.......................36 / 40
Prodrive;...............9.1..................... 34.9 / 41.3
StopTech;.............9.3.....................36 / 40
Stock;.................10.8.................. .43 / 43
...and COST!!!
Brembo F50;.......................US$2,995
Brembo Lotus;.....................US$2,595
Prodrive;.............................US$1,999
StopTech;...........................US$1,695
Stock with pads & fluid;....... US$130
R32 GTST
Front rotors (diam x thk) - 280×30
R32 GTR (Non V-Spec,)
Front rotors (diam x thk) - 296×32
R33 GTST
Front rotors (diam x thk) - 296×30 Different caliper to R32 GTR but same disc diameter.
R32 GTR V-Spec / R33 / 34 GTR with Brembos
Front rotors (diam x thk) - 324×30
R34 GTT
Front rotors (diam x thk) - 310x30
The calipers that suit larger diameter discs have longer mounting legs to space the caliper out further.
quote from: Brake Rotor / Caliper information - GTRCanada - Canada's premier skyline enthusiasts club