Rotors Are on Backwards

**LingLing** · 03-21-2010

While I was at Tom's last, he pointed out that the slotted rotors are on backwards

I'd like to keep them since they came on the car when I bought it and for the fact that they are Brembo rotors, but if I switched them around would it cause any weird vibrations?

Swifty1638 · 03-21-2010

Shouldn't. Post a pic of them installed right now. I doubt that Kevin or Mark would install them backwards, but hey, we all make mistakes.

**LingLing** · 03-21-2010

I just ran out and checked and they are on backwards. The highest point of the slot is leading, not the lowest. I always thought they looked kinda goofy hahaha. I'll have to switch those around when I pull the transmission.

**cmspaz** · 03-21-2010

I don't think it honestly matters all that much. They do their job whichever end leads...

It's the internal cooling vanes that matter.

**LingLing** · 03-22-2010

After I did some more digging on the intr0netz it sounds like it varies what brand they are. Apparently some brands are designed to be the opposite way of what you'd think they'd be. That, I never knew.

Matt D. · 03-22-2010

There has been talk forever as to which way the slot should go, but there is no definitive proof that one way works better or worse than the other. I had always been a fan of the inside of the slot leading so it acts like it would be pushing whatever material and gas it's scraping away toward the outside of the pad and rotor, but whatever.

**LingLing** · 03-22-2010

Quote:

Originally Posted by Matt D.

I had always been a fan of the inside of the slot leading so it acts like it would be pushing whatever material and gas it's scraping away toward the outside of the pad and rotor, but whatever.

+1, That makes the most sense to me too. But I have no idea whether these are the type of rotors that should be like this, or if they were accidentally put on backwards.

tpunx99GSX · 03-22-2010

Thinking Logically the leading should be the inside, Mainly like matt said, you want the dust/gasses/heat to be pushed outward away from being trapped towards the middle. Unless you do a lot of backwards racing like i do.
Ive actually pointed this out on not only jasons car but another guy in CAs car as well. Unsure how that mistake is made.

**LingLing** · 03-22-2010

Yep, I'm with ya there, too Tom. I always thought the highest point was suppose to be the trailing end. I'll probably end up switching those around when the trans comes out.

Matt D. · 03-22-2010

Quote:

Originally Posted by LingLing

+1, That makes the most sense to me too. But I have no idea whether these are the type of rotors that should be like this, or if they were accidentally put on backwards.

I've noticed that some (possibly cheap?) rotors are all made in one direction, so there is no differentiation between left and right, they all point the same direction, so one side of the car will be one way and the other side will be the complete opposite.

tpunx99GSX · 03-22-2010

Quote:

Originally Posted by Matt D.

I've noticed that some (possibly cheap?) rotors are all made in one direction, so there is no differentiation between left and right, they all point the same direction, so one side of the car will be one way and the other side will be the complete opposite.

I dont think they are the cheap ones. The first post stated they were brembos and all on backwards.

tpunx99GSX · 03-22-2010

Also what we are not thinking of (at least i wasnt) is the effect it has on the pads when the brakes are applied. If the leading edge is the top point, then it would cause the brake pads to pull towards the center of the wheel when the brakes are applied. But if the leading edge is the inside, it would cause the brake pads to push outward yes? Not sure which is better/worse. but another thought. I always figured the slots were for cooling/dusting purposes.

Matt D. · 03-22-2010

Doubt it has anything to do with an inward/outward force, I'd assume that would be negligible. The slots are designed to help keep the pads clean of dust/debris and help remove any gasses created by the high temps.

tpunx99GSX · 03-22-2010

yeah just a thought. then i will stick with my first answer.

Kevin 1G Drummer · 03-22-2010

They are not installed backwards. When I got the rotors, there was installation instructions that came in the box, and that's how it said they were supposed to be installed. I thought it seemed backwards as well, but that's how Brembo says they're supposed to be installed, so that's what I went with.

Matt D. · 03-22-2010

That's just it, I've seen instructions from manufacturers that say different things. I'm almost positive Brembo and Stoptech or Powerslot are opposites.

**Kracka** · 03-22-2010

Most brands don't matter, its the internal cooling vanes that need to be setup in the proper direction, but most of those aren't directional anyway unless you get into the high-end rotors. My advice is to just leave them since the pads have already bed in to the current rotors in the current direction.

**LingLing** · 03-22-2010

Quote:

Originally Posted by Kevin 1G Drummer

They are not installed backwards. When I got the rotors, there was installation instructions that came in the box, and that's how it said they were supposed to be installed. I thought it seemed backwards as well, but that's how Brembo says they're supposed to be installed, so that's what I went with.

Works for me!

**Kracka** · 03-22-2010

Brembo > Tom