CALL911

I guess I am still in the dark on this one. I have been told that slotting will help cool the rotors, and x-drilling makes little to no difference. From what you guys are saying, you are better to stick to just a plain rotor? The veining in the rotors are pretty much the same (between plain rotors and the slotted/X-drilled ones) from what I understand, and yes, I guess you could go crazy and run ducts to add more cool air to my rotors, but I would rather just change the brake set-up instead. When I changed to a X-drilled and slotted rotor, the brake fade I previously noticed under hard braking was eliminated. I didn't change airflow, or anything else. Yes the calipers were changed, and different pads, but the rating on the pads were the same as before, so how was the brake fade eliminated if slotting and X-drilling the rotors didn't do it? I am not trying to be a jerk here, I just don't understand.

jerminator96

Like i said before, the only reason for slotted rotors is for crappy pads that have outgassing issues. Though i do agree with you that the main reason people would want them is for looks, most people dont drive hard enough to encounter such problems (though there are exceptions )

CALL911

Well, I definatly don't drive my Z, the same way a soccer mom would take her minivan to the grocery store.

Anyone have a better explaination to my last reply?

Dave K

First of all... don't trust what the companies making these things tell you... because frankly they'll tell you whatever they think will make the sale. The primary reasons most folks think that slotting/cross drilling helps are twofold:
1) Whoever sold them the disks TOLD them they would help
2) They upgraded their brake system and are misattributing improved performance... it's the new calipers and pads that made the difference... not the rotors.

Every bit of real data I've seen has said that these days you are absolutely better off buying rotors with a solid braking surface for street cars... and even for many of the racing apps (if you're looking for optimum performance). GOOD rotors will have cool design tweaks like directional cooling vanes... but they'll still be solid. High end 6 piston designs will have other cool tweaks like floating hats... but they'll still have solid braking surfaces.

Now personally I think venting and cross drilling looks cool... gives your brakes some personality, so I don't have an issue with folks who go that route, I just don't believe it's anything but cosmetic.

CALL911

By vanes, are you referring to inside the rotor? If so, don't stock rotors come with the same vanes as say an aftermarket set from Baer?

Greed4Speed

Yes, inside the rotor. Our stock rotors are not directional. Baer and C5 rotors are.

Dave K

Right, it has to do with how efficiently your rotor pumps air from inside to out. Straight vanes will still work but vanes that follow more of an airfoil path will work significantly better. Even so... if you plan on a lot of hardcore braking (you're a road course guy for instance) then one of the mods on your short list should be ducting air to the inside of your rotors (just make sure you've got a screen in there to catch the odd stone or bird).

CALL911

So what I am gathering here is to upgrade the calipers, and pads, and as far as the rotors go, get plain ones that are directionally vaned. And then if I want to go crazy with it (which I don't), add air ducting to the rotors.

Are there any plain rotors that are directionally vaned, that are superior to others? Or are they all pretty much the same?

lefty

I usually have to get my rotors turned twice a year because they warp.slotting or crossdrilling wont help with that?Im tired of buying or turning the rotors.

96superZ

thanks guys, i have definetly reconsidered on buying the slotted/cross drilleds. ill prolly just buy some good plain rotors and get performance friction pads

Greed4Speed

Axxis makes nice pads too.

CALL911

Now I do know that the plain rotors I had, always seemed to warp even after a few months of use! (I am probably not an average driver on the road ) When I switched to my X-drilled and slotted, even after 15k and 3 years of severe abuse, they are not warped in the least bit! Perhaps it is the material the new ones were made from, or just an overall higher quality rotor, I am not sure.

Also if someone could explain to me, if X-drilled and slotted rotors do absolutly nothing to your stopping power, why do they put them on all the high end cars from the factory? (ex. Porsche, Lamborgini, Ferrari) Are you saying that even for high speed cars such as these that the rotors are purely cosmetical? I guess I am just not completly convinced here.

)2overt SS

The way I see it is...

Even though Ferrari's and Porche's might use slotted/drilled rotors, what does the C5R/C6R use?

Not sure about the C6R... but I'm pretty sure the C5R used solid rotors. So I don't think the top race engineers missed that

Dave K

From the reading I've done, the one valid performance reason to cross drill rotors is to reduce weight... perhaps that's the reasoning although I wouldn't say that it's NOT cosmetic - looks are even more important when you're paying 200+ thousand dollars for a car.

Greed4Speed

Porche rotor x-drills are ON the vanes. This make them stronger than the common x-drilled rotors you'll get for your f-bod. I have read an article where a Porche engineer was interviewed and he stated that Porche started offering x-drilled AS AN OPTION because people who spent that much on their car thought they needed them. Think about it, polished rims are an option, does this mean they have a performance benefit also? Well, Porche offers them.... Ya, leather interior makes it handle better too....Porche and Ferrari has it!

Call, your x-drilled rotors not warping is going to be due to more mass and/or better metallurgy. 15k in 3 years on a set of rotors isn't much milage. I put at least that much on in a year and I am far from easy on my brakes.

Yes, x-drilled will lighten the rotors, which isn't good for a street rotor. Remember, rotors are a heat sink!!!! The only place this is good is in highly competitive racing applications. Drag racing, and some higher end racing where they run carbon rotors etc.