hsv pb1 brakes

[VX2VESS]

this is daves cars from his ride post just to show the example.
http://www.excelerate.com.au/downloads/tigerss/SS%20brakes%20April%2007.JPG

Seems almost all these kits seen around on cars even VZ HSV's have them fitted this way, the wrong way around on the lhs. it appear to be a manuafactures kit problem, supplied like this...

this means that the skimmed crap and gases will not be thrown outwards, plus the angled vents inside the rotor would be drawing the air in the wrong direction, inwards not outwards to the outside of the rotor.

Under extreme braking such as a track day wouldn't this effect the braking? as the lhs rotor would be hotter etc than the rhs. must have some negative effect in these conditions faster pad wear and fade from one side.

should HSV replace all these?

[02vxss]

mate i have just purchased the same set, and you are right, the discs are not side preferenced. i had to go down to a local dealership to check out a vy clubby, and it was the same.

[Big123]

I just took these type of brakes off my VX and they are not left and right , Only rights all around etc .

Pretty stupid of PBR to do this .

[wablacksv8]

I have the PBR PK01 kit on my SV8 and I have LHS and RHS rotors. The direction is as per the first post. My way of thinking is the internal fins would scoop cool air into the rotors and the slots in this direction would act to skim the pads preventing glazing. Only my thoughts, anyone know for sure?

[DaveHAT]

I just took these type of brakes off my VX and they are not left and right , Only rights all around etc .

Pretty stupid of PBR to do this .

Whilst PBR did make the calipers I think Harrop machined the rotors. I'm fairly certain they were the tendered supplier of the HSV brake kits when these were manufactured.

Happy to be corrected ... :)

[VooDoo]

Go look at any stock HSV. They dont make left and right rotors. One will always be wrong. DBA do make directional ones though.

[wablacksv8]

Ordered from PBR front rotor part numbers are as follows:

PBR048SL
PBR048SR

(330mm with straight slots)

These part numbers are from my PBR invoice.

[SV805]

I didn't Think it really mattered what way the cut marks go on the actual disc's.....I thought it all had to do with what way the vents in between front and back of disc actually goes.........I can't see those from this photo.....

[Ken]

Unless the vehicle is travelling extremely fast (certainly more than legal speed) the direction of the vanes in the rotors has little or no effect ... especially on a road car that does not have ducts. At the rpm of a road-car wheel, the vanes create mainly turbulance rather than flow.
The grooves on the face of the rotors must always be opposed to the vanes or it will be a disaster waiting to happen.

However ... Almost all of the current Harrop kits are directional.
;)

[VX2VESS]

Unless the vehicle is travelling extremely fast (certainly more than legal speed) the direction of the vanes in the rotors has little or no effect ... especially on a road car that does not have ducts. At the rpm of a road-car wheel, the vanes create mainly turbulance rather than flow.
The grooves on the face of the rotors must always be opposed to the vanes or it will be a disaster waiting to happen.

However ... Almost all of the current Harrop kits are directional.
;)

Ken thats what i thought, why i mentioned track days which a lot do on here, at these speeds and lots of braking it would have some effect to performance between the sides. esp if you run some vent pipes to them.

not sure on the hsv rotors, but some DBA have straight venting inside the disc rotor so may not have an effect at left or right. but others have angled venting inside, i assume to cause some suction at speed. although the outside edge is round, if that edge was angled at each vane it should cause more suction, like the edge on some bike rotors, angled like that at the top of each vent running through the rotor.
do you think angle outside edge would cause more flow, create more negative air pressure on the ends of the vents?

[Ken]

... do you think angle outside edge would cause more flow, create more negative air pressure on the ends of the vents?

We have a test-rig that bolts to a lathe bed which enables us to reasonably simulate the rotor airflow (excluding wind from vehicle motion), and it is suprising how little effect some of the "fine detail" has. The wheel rim is probably the most restrictive item in the rotor air-flow.
Tweaking the vane edges will probably have some effect, but I doubt that it would be noticable (or even measurable) in the real-world race situation. A bigger thermal-displacement gain would probably be obtained by careful selection of rim design, and attention to pad selection & pull-back/knock-off.

[vxleather]

pull-back/knock-off.


Ken what is this ?

[VX2VESS]

thanks ken.. i have a few discs hanging around, if i get time one day i might frig around with it myself. must be a way to increase the fan effect, but all the manufacturers around all that can be done has been done.

So rims, you mean more clearance between the rim and rotors, large gaps inbetween the spokes, or rim spoke designs that creates a fan/suction effect. OR all three of the above

[Ken]

Ken what is this ?
How much distance the pad sits from the rotor when not being used. If it "rubs", extra heat is generated. A bigger distance will allow more cool air to circulate, but too much clearance gives a long pedal. Always a compromise.


thanks ken.. i have a few discs hanging around, if i get time one day i might frig around with it myself. must be a way to increase the fan effect, but all the manufacturers around all that can be done has been done.

So rims, you mean more clearance between the rim and rotors, large gaps inbetween the spokes, or rim spoke designs that creates a fan/suction effect. OR all three of the above

All three ... at least.