Originally Posted by svxcess

The guys at StopTech made tis very easy:

Stand facing the PASSENGER side front wheel

Salute the front wheel with your RIGHT hand

Now look at the angle of your hand, your fingers are pointing the direction that the slots should go.



On the DRIVER'S side, do the same thing only salute with your LEFT hand


Now wasn't that simple?? :)

.

Originally Posted by JaySVX

Well think about it. The spacer supports between the two plates on the front rotors are directional. Centrifugal force is going to pull air out, however if your turning against those spacers, the air isn't going to be able to escape as efficiently. The backs, i would just put on the same direction as the fronts.

Originally Posted by StopTech

The direction of the slots or hole pattern should not be used to determine what side of the vehicle to place a rotor. Different manufacturers may have different strategies for slot and hole patterns.

The only correct way to determine what side a directional rotor goes on is the internal vane direction.

Originally Posted by Brembo

Which direction should the discs rotate?
It is a popular misconception that the slots or drillings in 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 three vane types in use:

Straight
Pillar vane (comprised of many small posts)
Curved vane

The first two vane types are non-directional, and 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...

...all of Brembo's slotted discs are directional as well, regardless of the vane geometry. The discs should be installed such that the end of the slot nearest the outer edge of the disc contacts the pad first.

Originally Posted by LetItSnow

The material I've read in forums as well as name-brand pages (StopTech, Baer, etc.) indicates that the direction of the slots is often inconsequential, so long as the vanes are appropriately oriented.

Regarding StopTech's AeroRotors: <linky>



http://www.stoptech.com/tech_info/img/slotted_rotor.jpg

Regarding the StopTech guys' "salute-ion" (oh, I slay me), that may very well apply to their SVX rotors, but their webpage shows that even their own brand varies. :confused:

Brembo says half 'n' half of that, too: <linky>



:eek: It's probably safest to go by application, by brand.

Considering that the amount of gas that the slots are responsible for capturing is slight, that both ends of each slot are open to atmosphere, and that most of the way around, the slots are completely exposed, I'd follow the vanes first, manufacturer's guidance second, and (in indifference expressed by the components and their manufacturer) aesthetics third.

Naturally, as this defies some of the statements made in previous posts by a bunch of guys who don't just blindly hurl answers, I'm entirely interested in reading any opinions, quotes, or theories which parallel or contradict this one. :D