BTW- If anyone is curious I got them from APR for $90 each...and I bought a full set of Mintex Red Box pads from Adrionac (sp?).

Anyhow here's the question...which one is the left and which one is the right rotor. They both look like they'd fit on either hub...but the hole pattern seems to indicate that there is a left and a right side...how do I tell which is which.

Here's what I figure with the rotor facing me as it would sit on the hub there is a pattern of 4 holes then 5 holes...which repeats over and over making a pattern that looks very natural if it were turning clockwise..I assume this is intended direction of rotation? In this configuration the O in Brembo would be turning forward moving from left to right...I'm reffering the the Brembo stamp on the top of the disc.

That aside is there anything else I should look out for...I heard something about damaging the wheel bearing once...maybe I'll check the archives.

Thanks in Advance,

James R.

99 1.8TMS (Brembo Rotors, Mintex Red Box, Bilstein Shocks, Neuspeed Sport Springs and Front Anti Sway Bar, Neuspeed 0.8 Bar Chip, Ram Air Filter, Remus Exhaust, Ronal R-28's 17" x 8.5", Euro Corners + Markers...tint all the way around and probably some other stuff I've missed.)

The vanes in between the rotor halves should be curved. The holes
are probably also curved as they go through the space between the
vanes. The vanes are open more at the outside edge of the rotor
than the inside.

If you look at the rotors, turning them in one direction would seem
to "catch" cooling air, as the vanes at the outside edge of the rotor
would seem to try and force air into the rotor. This is NOT the way
they should be mounted, even though it might make sense to try
and catch the air.

When the rotor is spinning, air would be forced up and out the vanes
through centrifugal force. If the vanes were "catching" air from the
outside, then this air coming in and the air being forced out through
centrifugal force would meet and greatly reduce cooling.

If you look at the rotor, when it's spinning the openings in the vanes
on the outside of the rotor should be facing backwards (or trailing the
direction of rotation).

Hope this helps.

Curt

<center><img src="http://131.107.68.28/a4org/rotors.jpg"></center><p>I tried looking at the vanes, but they are straight...they do get smaller at the bottom but have no curvature at all, at least none that I can discern. So which way do they go? Intuition would tell me that this picture is of the Right rotor, but I'd like to know for sure as intuition isn't going to cut it when it comes to really important stuff like brakes.

Regards,

James R.
99 1.8TMS

nt

The 5 hole pattern should lead through the caliper with the hole closest to the hub.

nt

Take a look at the drill pattern on the rotor. Notice how there is a curved line of holes from the hub outward. The curve should arch backward from the top of the hub when the rotor is mounted. HTH

Chris

The curve i am talking about is the 5 hole curve followed by the 4 hole curve.