I've seen slotted rotors mounted with the slots facing forward and mounted facing rearwards My instructions shows that they should be mounted with the slots sweeping towards the rear of the car. Who is right??

 

As the slots are for heat disapation, I'd figure it could go either way theoretically....but I've only seen them like this so the lower part would contact the pad first, so to speak.

R

 

You mean swept towards the rear, right? That's what my instructions says (picture showing swept rear indicating "right side&quot

 

Most rotors are marked as being LEFT or RIGHT so you should follow the instructions and/or rotor markings.

Why? Because the slots don't matter but the internal cooling vanes do. So, if the rotor has directional internal cooling vanes, it is VERY important to have them rotating in the correct direction, otherwise, the rotors will run MUCH hotter than you want.

 

>>Most rotors are marked as being LEFT or RIGHT so you should follow the instructions and/or rotor markings.
>>
>>Why? Because the slots don't matter but the internal cooling vanes do. So, if the rotor has directional internal cooling vanes, it is VERY important to have them rotating in the correct direction, otherwise, the rotors will run MUCH hotter than you want.
The internal cooling vanes in mine are radial and not directional. The instruction consists of a picture showing an image of two rotors with respective "right" and "left" under each. As previously mentioned, it indicates that the slots be swepted towards the rear if when they labeled "right", they meant the right side of the car when facing towards the front.

 

Slotting the surfaces of brake rotors improves their performance in extreme conditions by allowing gasses given off by the superheated pads and rotors to escape. With non-slotted rotors, the gasses can build up between the surfaces and lessen the contact between them. Cross-drilling has the same effect, but is only recommended for solid rotors.

 

Seems like your instructions are pretty clear then

Whose rotors did you get?

 

>>Seems like your instructions are pretty clear then
>>
>>Whose rotors did you get?


I got them from Mini-mania...I'm surprised that no one has a definitive answer to why people have mounted both ways....and on some pretty exotic machines too.

 

>>Slotting the surfaces of brake rotors improves their performance in extreme conditions by allowing gasses given off by the superheated pads and rotors to escape. With non-slotted rotors, the gasses can build up between the surfaces and lessen the contact between them. Cross-drilling has the same effect, but is only recommended for solid rotors.


Thanks...I knew that...that's why I bought them

 

the natural way a rotating disc would fling off gasses is from the center to the outside (duh!) so orient the grooves so they sweep the gasses from the center toward the outside

 

>>the natural way a rotating disc would fling off gasses is from the center to the outside (duh!) so orient the grooves so they sweep the gasses from the center toward the outside


Fling off gasses from center to out side I get but what does that have to do with the directions of the slots? Even it's backwards, the centrifugal forces will force it to out wards anyway

 

I want to get the same set too. It's a simple upgrade that wont add the weight that the oversized rotors would.

EDIT: Think of the slotted rotor as a phonograph record. Spin it in the direction it would turn when the car moves forward. The groove should carry the 'needle' from the inside diameter to the outside edge as the rotor spins. Not only are you clearing gasses from the surfaces, but you help to sweep out abraded pad and rotor debris via the slots that would lessen the brake effectiveness as well.

_________________
'03 MCS, Dk Silver, 17" R85s, NAV, DSC (often turned off!), Packs #1 and #3, Rally lights, etc, etc. Fulton, MD. FRS 7-21

 

How does the weight compare to the stock rotors and how is the finish? Any better looking than stock (rusty)?

 

Slots should curve from center going out away from the direction of rotation.

Looking from the side of the car at the top of the rotor,with the wheel/rotor rotation in this direction >>> the slots would be >>>>.

 

That's what I've always understood. I guess what I'm asking is if anyone know why some modded "centerfolds" appear to have the rotors in the "wrong" direction. Did they make a mistake Does anyone know of a ligit reason if there is one?

 

>>That's what I've always understood. I guess what I'm asking is if anyone know why some modded "centerfolds" appear to have the rotors in the "wrong" direction. Did they make a mistake Does anyone know of a ligit reason if there is one?
>>

Photo "centerfolds" are sometimes printed backwards (Mirror image) so the car will appear to face the direction they want on the page. Sometimes they do this unintentionally. In either case, this changes the apparent direction of rotation. This may be what you have observed.

 

You have solved the riddle I was hoping someone would come up with a good excuse

 

Well, as far as I know, there is no real difference in the direction of the slots, that is what I was trying to say earlier.

I have 3 cars with slotted rotors and 2 (both from Powerslot) are done one way and one the other way (from Brembo). They are all mounted correctly.

I have heard that you get a better bite into the pad if the slot tip into the pad (forward at the top). But I believe the differences are minor.

Anway, the slots are indeed done both ways depending on the manufacturer.

Sorry, but I don't think there is a good and definitive answer to your question.

 

>>How is the finish? Any better looking than stock (rusty)?

Note that for the nice looking coating on Powerslot rotors, it melts right off after some hard use and they rust almost immediately.

 

>>Well, as far as I know, there is no real difference in the direction of the slots, that is what I was trying to say earlier.
>>
>>I have 3 cars with slotted rotors and 2 (both from Powerslot) are done one way and one the other way (from Brembo). They are all mounted correctly.
>>
>>I have heard that you get a better bite into the pad if the slot tip into the pad (forward at the top). But I believe the differences are minor.
>>
>>Anway, the slots are indeed done both ways depending on the manufacturer.
>>
>>Sorry, but I don't think there is a good and definitive answer to your question.


Hey..Thanks for information.