Looked at a magazine today....and it showed a big brakes conversion...and they mounted the slotted rotors backwards, and called it J-spec. Because thats what japanese circuit racing teams do? Anyone heard of this, know why its done, good or bad?

 

Whatchoo talkin' 'bout Willis?

 

That's because in Japan, wheels spin the opposite direction compared to wheels the US. It's like flushing a toilet in Australia.

 

LOL...

[QUOTEThat's because in Japan, wheels spin the opposite direction compared to wheels the US. It's like flushing a toilet in Australia.[/QUOTE]

 

actually, my pops and I accidentally mounted the brembo kit backwards on his cobra...kinda funny....fortuantely we were the only ones who noticed

 

I dont know what was done.

 

The direction in which the slots on the outside of the rotor faces is inconsequential, as each company has their own "theory" of what works best, and in some cases, the same company may have some rotors where the slots face one direction, and other rotors where they face the opposite direction.

For directionally vented rotors, the key is the direction in which the internal vanes point. You want to install directionally vented rotors such that the internal vanes point towards the rear of the vehicle. For example, if you are installing a rotor on the left side of the car, the internal vanes should point clockwise as if you were spinning a "pinwheel" _counterclockwise_.

For rotors which are vented, but not directionally vented (i.e. the vanes are perpendicular), then it really doesn't matter which way you install the rotor, generally speaking.

One theory is that if the external slots point to the rear of the car, that the pads will outgas more efficiently (similar to directional venting). The other theory is that if the slots point to the front of the car, that you will have improved initial bite, as the slots will "cut" into the pad (deglazing it) more aggressively.

My own theory is that only slotted rotors which are hard-edge slotted (thin slots with sharp edges) are worth running for a race application. On the street, any type of slotted rotor will improve initial bite and wet performance, and only for street use do I "not have issues with" using a typical run-of-the-mill slotted rotor, though I don't personally consider it worth the additional cost.

JMO... -Andie