Killer Deal on 300c and 300 Cross-drilled Slotted Rotors

[marlinspike]

Originally Posted by DZeckhausen

Slotted rotors should be cut in a direction opposite to the internal vanes so that each slot is supported by several vanes, which act as reinforcement.

What are your thoughts on ATE powerdiscs where the slots sorta go all over?

[Meister]

Originally Posted by shanemcse

I just picked these up in person. I have them if anybody has any questions...

Please give us your impressions after installing them.

And if you're not aware of it, the best brake bedding "how to" I've seen is posted on Dave Zeckhausen's Web site. Check it out and bed 'em in right.

[DZeckhausen]

Originally Posted by marlinspike

What are your thoughts on ATE powerdiscs where the slots sorta go all over?

The ATE Powerdisc rotors with the "mutipurpose groove", for those who haven't seen them, use a unique slot pattern that resembles an atom with orbiting electrons. These are often referred to as the "nuclear rotors."



The steep angle of the grooves and the fact that they make these only for rotors that are non-directional (meaning the internal vanes point straight out from the center of the rotor and there is no "left" or "right") ensures that the rotors are not weakened by a slot running in the same direction as an internal vane.

The Powerdisc pattern is an attempt to break out of a commodity market with something that is recognizable, not only by the packaging, but also once mounted to the car. Brake dyno tests show no significant advantage in bite over traditional slotting patterns, so the "atomic" pattern is nothing more than a marketing gimmick.

Since ATE doesn't use a Dacromet coating like the OEM factory rotors, these tend to rust in the grooves, in the internal vanes, in the center hub, and any other unswept area, often causing an orange "ring of shame" that is visible with open wheel designs. Not the sort of thing you want on a show car.

[shanemcse]

I was going to take a picture of them and post it but the picture in the 1st post is exactly what they look like. Irotors.com does offer different designs either with all holes or with all slots. I just don't believe having holes and slots is a bad thing. If it was a bad idea then why do so many places offer them?

For example here are some pretty popular sites that offer rotors with holes and slots.

http://www.tirerack.com/brakes/brake...oStop+II+Rotor

http://baer.com/cgi-bin/htmlos.exe/0...63509000004772

http://www.nationalfleetparts.com/rotors.asp

I am not trying to argue but I just would like some kind of proof seeing how so many places offer them.

[steve 300c]

Its starting to smell like a group buy in here!

[Meister]

Originally Posted by shanemcse

...I just don't believe having holes and slots is a bad thing. If it was a bad idea then why do so many places offer them?

For example here are some pretty popular sites that offer rotors with holes and slots.

http://www.tirerack.com/brakes/brake...oStop+II+Rotor
...

I am not trying to argue but I just would like some kind of proof seeing how so many places offer them.

Hi shane. I'm here to learn, and very much appreciate you and the information you're sharing. So don't take anything I say here as being argumentative, or worse. Because it's not.

This forum is "blessed", if I can use that word here, to have one of the brake industry's foremost wizards in close attendance, Dave Zeckhausen of Zeckhausen Racing. He's "in the trenches" with racers from all aspects of motorsport on a regular basis, sees the effects of good & bad design on a near-daily basis, and is bright enough to make pertinent application of this "insider" information.

So if I'm going to be setting up a car for racing, Dave's word is gospel for me - his credibility is sky high. I need no second opinion.

So I suppose the question is, how closely do I need to follow what Dave knows to be best for track applications if I'm only going to run my car on the street? For me, the answer is probably 100%, because of my God-given wild hair that I'll never outgrow...I manage to find sections of road that enable me to put my 300C through its paces in a very demanding manner with some regularity. For others, it may be less crucial.

It's interesting, shane, that your very first reference, the one from Tire Rack, supports Dave's findings by offering a faux drilled, slotted rotor, since cross-drilled rotors, especially when combined with slotting, tend to crack. The "holes" are merely cosmetic dimples in the rotor's surface. Here's the short version of that product description:

From Tire Rack:
http://www.tirerack.com/brakes/brak...roStop+II+Rotor

"It’s a fact that venting the gas emitted by hot brake pads improves overall brake performance and helps minimize fade. At one time the conventional wisdom in racing circles was to cross-drill brake rotors to aid cooling and eliminate the gas emitted by brake pads. However, today’s elite teams in open wheel, Indy and Trans Am racing are moving away from crack prone, cross-drilled brake rotors in favor of rotors modified with a fatigue resistant slotting process.

Power Slot’s ProStop II rotors were developed to combine the look of a cross-drilled rotor with the durability of a slotted rotor. ProStop II rotors are enhanced with a series of four drilled “dimples” that look like cross-drilled holes (especially when brake dust is collected at the bottom of the dimples after several hundred miles of driving). By installing ProStop II rotors, a driver can have the “look” of a cross-drilled rotor and the performance of a slotted rotor without compromising the structural integrity of the rotor. ProStop II rotors with their faux-drilled dimple treatment are specifically designed to provide a safer alternative to drilling crack prone holes through cast iron rotors and offer a more aggressive appearance than the original ProStop rotors.

Power Slot's slotting process and faux-drilled treatment removes less heat absorbing mass and less of the rotor’s surface area than conventional cross drilling to help maintain the highest possible co-efficient of friction for the brake pads to work against."


If the rotors you've purchased are truly cross-drilled, as well as being slotted, then I suppose the question is "will they hold up just fine under normal street use?". My guess is yes. How would they fare under very demanding street and back road use? Probably not very well, from what we've read.

So they may be perfectly fine for you, and perhaps many others here as well - they look great, they're treated against rust, and appear, from reading, to have good metal in them.

If I, however, because of my need for speed, were to quickly grab a set of rotors just from the offerings you've presented I'd choose the Power Slot ProStop II's - for the reasons clearly laid out in the above quote.

Just my thoughts. Please keep on posting.

[Goose]

DZeckhausen, Could you tell us your recomendations on a good set of rotors?

Thank you.

Originally Posted by DZeckhausen

The ATE Powerdisc rotors with the "mutipurpose groove", for those who haven't seen them, use a unique slot pattern that resembles an atom with orbiting electrons. These are often referred to as the "nuclear rotors."



The steep angle of the grooves and the fact that they make these only for rotors that are non-directional (meaning the internal vanes point straight out from the center of the rotor and there is no "left" or "right") ensures that the rotors are not weakened by a slot running in the same direction as an internal vane.

The Powerdisc pattern is an attempt to break out of a commodity market with something that is recognizable, not only by the packaging, but also once mounted to the car. Brake dyno tests show no significant advantage in bite over traditional slotting patterns, so the "atomic" pattern is nothing more than a marketing gimmick.

Since ATE doesn't use a Dacromet coating like the OEM factory rotors, these tend to rust in the grooves, in the internal vanes, in the center hub, and any other unswept area, often causing an orange "ring of shame" that is visible with open wheel designs. Not the sort of thing you want on a show car.

[DZeckhausen]

Originally Posted by shanemcse

I just don't believe having holes and slots is a bad thing. If it was a bad idea then why do so many places offer them?

Because people are gullible and will buy them.

Do a quick Google search on the "Tornado Fuel Saver" and see how many places offer this piece of junk. Here's a product that is nothing but a scam and Consumer Reports recently documented that it reduces the gas mileage on your car. Yet even Amazon.com sells them!

You can't assume, because lots of places sell a product, that the product is any good. The only thing you can conclude is that the product is profitable to sell.

[DZeckhausen]

Originally Posted by Goose

DZeckhausen, Could you tell us your recomendations on a good set of rotors?

I'm not aware of any good aftermarket rotors for the 300C yet. At this point, if my stock rotors were worn out, I would buy a new set of factory rotors from a discount Mopar dealer.

I wouldn't be surprised if Brembo and/or Powerslot have replacement rotors for the 300C in the development pipeline.

[marlinspike]

Originally Posted by shanemcse

If it was a bad idea then why do so many places offer them?

Um.....you're...you're kidding right?