Brake specifications

From R31 Skyline Club Wiki


Front brake all Australian delivered cars except GTS[edit]

File:Slimlinecolettecaliper.jpg
Front caliper assembly
Front
  • Brake model: Girlock Slimline Colette
  • Pad: Width x thickness x length = 43 x 11 x 129 mm (1.69 x 0.43 x 5.08 in)
  • Rotor outer diameter: 250 mm (9.84 in)
  • Caliper inner diameter: 54.0 mm (2.126 in)

The caliper assembly consists of two main components. The cast iron anchor plate, and the alloy housing. The anchor plate is bolted to the front strut stub axle boss, whilst the housing slides within the anchor plate by means of two guide pins. Guide pin boots prevent dirt ingress and self-locking bolts secure the alloy housing to the guide pins.

This type of caliper operates on the single piston principle, with the housing incorporating the hydraulic piston and seal. When hydralic pressure is applied, the single piston forces the inner pad against the disc, with the housing reacting to pull the outer pad towards the disc. The pressure on both sides of the disc is then equal.

When the pressure is released, the piston seal fitted in the bore of the housing retracts the piston a small amount, which allows the moving parts to relax sufficiently for the pads to remain in close proximity to the disc without dragging. Adjustment for wear is automatic.

Both inner and outer pad assemblies take the rotational thrust directly on to the anchor plate. Each pad incorporates a torsional spring to eliminate housing and pad rattles.


Rear brake[edit]

File:Rearcaliperassembly.jpg
Rear caliper assembly
File:BrakesozR31back.jpg
Rear
  • Brake model: Girlock Colette
  • Pad: Width x thickness x length = 32 x 7.5 x 108 (1.26 x 0.29 x 4.25 in)
  • Drum inner diameter/Rotor outer diameter: 260 mm (10.24 in)
  • Caliper inner diameter: 38.0 mm (1.50 in)


The Girlock rear brake assembly features a self adjusting integral park brake mechanism which utilizes the service brake disc pads.

This system is similar to that used on other local and imported models.


Brake System[edit]

Common to all AusDel R31 Pintara/Skyline models;

  • Master cylinder: PBR P10226
  • Bore diameter: 22.2 mm (0.875 in)


  • Brake booster model: ISOVAC VH5527
  • Diaphragm diameter: 230 mm (9.06 in)


AAD (formerly ProTex, https://www.aad.com.au/) have these parts available, with the re-manufactured brake booster part# being VH5527R

GTS1, GTS2[edit]

File:BrakesHR31front.jpg
GTS Front
File:BrakesozR31back.jpg
GTS Rear
File:BrakesHR31front.jpg
HR31 Front
File:BrakesHR31back.jpg
HR31 Rear

Front brake

  • Brake model: CL28VB
  • Pad replacement minimum thickness: 3.0 mm (0.118 in)
  • Rotor repair limit:

Maximum runout 0.07 mm (0.0028 in)

New thickness 22.0 mm (0.866 in)

Minimum thickness 20.0 mm (0.787 in)

  • Pad: Width x thickness x length

Inner 43 x 11 x 126.5 mm

Outer 43 x 11 x 129 mm

  • Rotor outer diameter: 274 mm
  • Caliper inner diameter: 60.6 mm


Exploded view of GTS caliper

File:Exploded-brake.jpg

Replacement rotors[edit]

Model Year F/R Type Cat.No. Slotted only Slotted/Cross drilled Vented/Solid A B C D E F
R31 except GTS 86-90 F Solid 616 X X Vented 250 48 22 20 hub type 4
R31 GTS Local and some Import 86-90 F Vented 924 X X Vented 274 47 22 20 68 4
R31 all Local and some Import 86-90 R Solid 616 - X Solid 260 60 10.4 9.4 68 4
  • A = Diameter
  • B = Original Height
  • C = Original Thickness
  • D = Minimum thickness for replacement
  • E = Centre Hole
  • F = Number of Holes