Orientation of Performance Friction discs

[breeze]

I'm in the process of fitting new Performance Friction discs to my car to replace the AP items that came with the AP kit.

Does anybody know which way the slots in the disc should be facing?

Nothing in the box to say which way although the APs that came off 'faced into the pad' rather than 'alongside' it if that makes sense...

Discs are the two piece slotted items here:
http://www.performancefrictionbrakes.com.au/products.php?pageId=42

Any help much appreciated!

[3wheels3]

They seem to have left/right product codes from your link

[shimmy]

https://nam3forum.com/forums/forum/csl-register/general/csl-technical-area/508724-pf-discs-urgent-help-please

grooves face opposite to AP discs

at the top they are ponting back towards the callpiers on the front

[shimmy]

[Nords]

That's it Shimmy, same as mine!



:thumbs:

[northernjim]

you can have the grooves facing which ever way you like as long as the vanes inside the discs are facing the right way....

[shimmy]

you can have the grooves facing which ever way you like as long as the vanes inside the discs are facing the right way....

not a lot of help that comment NJ as firstly unless you tell us which way the viens are meant to point

and a misleading answer tbh as the discs in question the grooves should only go one way as they are fixed to the veins:birdman:



:hahaha:

[northernjim]

I know it was a bit misleading :hahaha::clown:


what I mean is that the vanes inside the discs are there to cool the discs down, and that the airflow thru the vanes should go from the centre of the disc to the outside.... [ which is where you would fit any cooling ducts to the back of your discs]


ballcocks! AP will be better telling you than me- taken from there brake fitting guide -

AP Racing Formula Big Brake Kit Owner’s Manual
P14.070 / issue 1 Page 6 March 2004

DISC ROTATION DIRECTION

It is a popular misconception that the slots on the surface or drillings through a disc
determine the direction of rotation. In truth, for an internally vented disc, the geometry of the
vanes dictates the direction of rotation.

There are two types of ventilated disc design vane types in use:

n Straight

n Curved vane

The straight vane types are non-directional (identifiable because both discs will be listed
under the same part number), and hence can be used on either side of the vehicle.

The curved vane disc, however, is directional. A curved vane disc must be installed with the
vanes running back from the inside to outside diameters in the direction of rotation (see
the figure).
Orientating the disc in this manner creates a centrifugal pump. The rotation of the disc
causes air to be pumped from the centre of the disc, through the vanes, and out through the
outside diameter of the disc. This greatly enhances the disc’s ability to dissipate heat.
That is the important bit....

To aid cooling, some vehicle manufacturers include scoops to direct airflow to the disc
inner diameter. If desired, ducting can also be added to allow the disc to run at optimum

temperature, especially when the vehicle is used for circuit track day events.


http://www.apracing.com/drawings/for...it%20guide.pdf

page 6 of this guide shows this info and a good picture too that i couldn't copy....

[northernjim]

not a lot of help that comment NJ as firstly unless you tell us which way the viens are meant to point

and a misleading answer tbh as the discs in question the grooves should only go one way as they are fixed to the veins:birdman:



:hahaha:

early AP brakes have the grooves facing one way, later ones they go the other... I meant that you can machine in grooves however you like so long as the vanes inside are going the right way:beer:

[TANKSLAPPER]

HAVE YOU GOT IN THE GROOVE YET ?

I have, nice bottle of Chianti ! !

[breeze]

Superb effort gents - just what I needed.

Despite gettign gutterly drenched in the rain discs and pads (RS29s) are on and bedding in nicely.
:beer:

[Nords]

I know it was a bit misleading :hahaha::clown:


what I mean is that the vanes inside the discs are there to cool the discs down, and that the airflow thru the vanes should go from the centre of the disc to the outside.... [ which is where you would fit any cooling ducts to the back of your discs]


ballcocks! AP will be better telling you than me- taken from there brake fitting guide -

AP Racing Formula Big Brake Kit Owner’s Manual
P14.070 / issue 1 Page 6 March 2004

DISC ROTATION DIRECTION

It is a popular misconception that the slots on the surface or drillings through a disc
determine the direction of rotation. In truth, for an internally vented disc, the geometry of the
vanes dictates the direction of rotation.

There are two types of ventilated disc design vane types in use:

n Straight

n Curved vane

The straight vane types are non-directional (identifiable because both discs will be listed

under the same part number), and hence can be used on either side of the vehicle.

The curved vane disc, however, is directional. A curved vane disc must be installed with the

vanes running back from the inside to outside diameters in the direction of rotation (see
the figure).
Orientating the disc in this manner creates a centrifugal pump. The rotation of the disc
causes air to be pumped from the centre of the disc, through the vanes, and out through the
outside diameter of the disc. This greatly enhances the disc’s ability to dissipate heat.
That is the important bit....

To aid cooling, some vehicle manufacturers include scoops to direct airflow to the disc

inner diameter. If desired, ducting can also be added to allow the disc to run at optimum

temperature, especially when the vehicle is used for circuit track day events.

http://www.apracing.com/drawings/for...it%20guide.pdf

page 6 of this guide shows this info and a good picture too that i couldn't copy....

Well it would be if AP discs weren't made out of cheese (early sets anyway!) This is a thread about Performance Friction discs, admitably with excellent AP calipers!

I tried a 997RS recently with std calipers and the ceramic discs. Although much better in terms of being progressive, I think my RS29 in AP Calipers as just as good, if not better!

[s.mac]

Ras did you tighten to a specific torque setting ?? if yes what was it

[shimmy]

Ras did you tighten to a specific torque setting ?? if yes what was it

the disc bolts are torqued i think to 14nm, hand tight virtually

[SpineOnABap]

Shimmy, you're not running Lo-Spec calipers are you?!