I painted my new cross drilled/slotted GM Delco rotors last week. I know forgot which rotor was left and which was right. Anyone knows the correct direction or does it really matter as long as I have them all in the same direction.

Thanks

 

On the driver's side, the slot should start at the top left, and head down towards the right.... like the backslash symbol: \

EDIT: Realized this will prolly result in a question The passenger side is opposite (if manufactured correctly, and purchased correctly). The passenger side should be: / Basically, the C6Z06 is wrong..... as is the C6Z51, I believe (but not 100% sure). But then, they're drilled and not slotted

- Colby

 

The direction the slots go is not as important as the direction of the internal vanes, which should be opposite the direction of rotation.
Either way, it is probably not critical since GM only makes one rotor for both sides of the Z06. If you look at the factory rotors, they go in opposite directions on each side of the car.

 

The direction of the slots doesn't matter, and in fact is not even consistent among manufacturers. The direction of the vanes (between the rotor plates) is what matters. If they are straight, then it doesn't matter how you install them. If they are angled, they should be installed so that they scoop air in the normal forward motion (i.e., facing forward at the 6 o'clock position and facing aft at the 12 o'clock position).

 

Thanks. I've seen so may pictures of rotors on the forum, some have the slots going one way on the drivers front, while others have it going the opposite. I'll check th directions of the vains .

 

Right. The slots don't go in the direction of the vanes. My Stoptechs, or example, have the slots going as I described above, but the vanes should NOT go that way. Vanes suck air in from the hub area and shoot it out the outer diameter (theoretically). So, the visible part of the vane (at the outside of the rotor) is the exit and should point toward the rear of the car. Like this for the driver's side:

*Well that didn't work.

Trying again as viewed from the top/front of the rotor as if you could see through it (the asterisks represent the vane):

FRONT................................... ....................REAR

---------------------------*
-----------------------*
-------------------*

If you envision the scooping from the inside of the rotor, this correct. It slices the air, and throws it out the outside of the rotor as it spins (like an impeller kinda). What you don't want (again, theoretically) is to scoop it from the outside and pull it into the hub area.... this is NOT what the brake duct engineers wanted. BUT it IS what GM has done on the C6Z51 and Z06. One part # for front and one for rear...... lame by Stoptech and Brembo standards.

- Colby

 

The vanes are angled. It makes sense the vanes should face foward. The slot on the drivers front rotor is top left and bottom right. like \

Thanks everyone......

 

I'm confused, vanes foward or back?

 

Page 11 of this Stoptech PDF shows it perfectly for the passenger side....

http://www.stoptech.com/tech_info/ma...C_03-02-06.pdf

- Colby

 

Okay, the pictures on page 13 and 14 helped out.

thanks

 

Be very careful, like stated above, there is no rule among manufacturers. My Brembo's came with this statement:

"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. Orienting the disc in the manner creates a centrifugal pump. The rotation of the disc causes air to be pumped from the center 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.

Additionally, 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."

So on the Brembo's (and be careful here too, many "brake manufacturers" that claim to be Brembo are actually buying 'blanks' and cutting/drilling them themselves) the pad surface slots are oriented so that the top of the slot contacts the pad first in normal direction. Other manufacturers say the exact opposite. You will get many different answers to this question not because we just don't know; in this case there are many different correct answers. YMMV

Good Luck.

 

That's the best picture of it right there.

 

This one may be even easier to understand: http://www.stoptech.com/tech_info/faqs.shtml#16

 

There on the same way as the pics. thanks everyone for helping out..


John