Grooved Discs ... which way around ??

[grinder]

Hiya ,

I have some grooved and drilled front discs for my FC

But im trying to figure out which of the front wheels it should go on

Attached is a pic of the actual disc , which i took

So is it a passenger side one , or a drivers side one

Im sure that both discs are grooved in different directions aswell

Thanks

Stu

[Prof]

Mine had L and R stamped on them somewhere on the disk - (could be inside the hub mounting part) - but the vents generally go in the direction of motion (like waves hitting the beach)
 
Also - just by way of addendum - the screw holes are off centre - so if you do use them, they will only fit one way around.

[grinder]

handy to know about the holes being offset

and with the L and R .. is that stood at the back of the car or the front ?

And with the wave theory .. the piccy on the left ( single disc ) do we assume that drivers side ( wheel will go clock wise as you move forward )

And thats a speedy response Dave

[grinder]

just so that i can find it again .. here is when i did it last time

http://www.mazdarotaryclub.com/forums/showthread.php?t=55775

[lockwood77]

I\'ve read both way - Dixcel say mount them so that the outer-edge of the disc has the groove furthest forward, so in your first pic, that would indeed be driver side. The grooves would kind of be like your arms doing front crawl when swimming!

That said, I\'ve always mounted mine the other way, so the grooves are "swept back" as the wheel rotates (going forward). Obviously that means the single disc pic would be passenger side!

[GrimR33per]

The direction of rotation is dictated by the vents in the centre of the disc not the grooves you are looking at.

[GrimR33per]

This will help..

http://www.apracing.com/drawings/cp3718-2020~1CD.pdf

[GrimR33per]

And a pic for inner Vane rotation.....

[grinder]

OMG well thats more confusing !! LOL

[wolfie1]

the single disc pic you put up would be a passenger side disc

[Prof]

I concur with wolfie - just had a look at mine in the dark (with a torch) and the single pic shows passenger, the other shows drivers and passenger side from left to right

[GrimR33per]

The grooves nearly always run into the pads. Check your vanes inside before you fit.  If they are straight vanes then they can go anyway you want.

[B.Martin]

Should sticky this, good advice for anyone with similar problems.

[batman]

i was told the groves go anyway forwards or back wards its the vents in side the disc that matter they should curve forwards like front crawl pulling air into the disc .

[Bobbit]

First pics you put up is for passengers side, 2nd pic left to right, passengers and then drivers side.
As i understand it the grooves are to help displace any trapped gasses, so the inner part of the disc would hit the pad first and any trapped gas would flow backwards away from the pad.