I did some reading and from what I saw it seems like they are actually not a great idea and they add that drilled rotors are even worse because they make the rotor more fragile.

Thoughts?

slotted is a good idea, the only time you should use cross drilled rotors is if its an extremely large and expensive rotor thats actually been designed to be drilled, if you grab a set from ebay or a set for your car I wouldn't trust them, if you had say...a Porsche and it came stock with drilled then I would use them.

slotted gives you a decent middle ground where fracturing under stress is rare.

As Terry stated, it depends on quality, I've had the same drilled/slotted rotors that came with the Baer big brake kit since it was new(5 years and counting), while I have not abused the car on a road course, they have seen countless 100+ mph decels at the track, no cracks, no warping.

I wouldn't hesitate to use a cross drilled rotor from a company such as Brembo but definitely not from some generic ebay company.

Baer = engineered to be drilled, Brembo = engineered to be drilled, Project U = engineered to be drilled

Almost any brand to replace your oem rotors with out an actual big brake upgrade = wouldn't trust it with MY life.

Econo box blank rotors are plenty for a street car, if youve ever got your rotor to glow red then you should probably consider some sort of vented setup.

But slotted and drilled look so badass ...

Unno about you guys but I personally don't push my car to the point where I would notice the difference between regular and drilled rotors. However I'm sure some one designed them with a purpose so I have to agree with Terry. If they're designed and engineered to be drilled then I'm sure the effort used to make them drilled is worth it

Good job gents. I agree 100% with everything said here because it is true.

I also agree with you 100% but do they actually provide any value.

My understanding is that ebay rotors are just drilled, where as brand name are cast to be drilled.

One of the main points was look at cars that come factory with big brakes and the fact that a lot of them just use blank rotors.

Also the fact that you are actually loosing surface area when you switch to a slotted/drilled rotor so you are reducing your stopping power.

Also this:

F1 cars also get rebuilt after every race, if you want a proper comparison then stick to vehicles available as a road legal DD.

They make a huge difference over stock rotors. Would i put them on a F1 car frack no.but i also wouldnt put F1 brakes on my car. Full ceramic brakes are great if you are pulling your car down from 200km/h on every corner. But daily driving you wont generate enough heat in them to stop you properly.

There is a company called roto-tech in T.O that make cross drilled I have been using them for at least 12 years with no issues. Not for F1 racing but great for everyday use and some spirited driving.

Terry, In most cases I would agree with you but in this case we are looking at braking effectiveness.
Thanks for that Stephen, I was unsure as to how carbon ceramic brakes worked exactly and didn't realize they hot to be really hot to work well.I also hear they are super noizy.
If heating would be an issue do you think F1 cars would use blanks?

Also a lot of the high end cars at the 24h lemans use blanks. I can't think of a better test of endurance and strength. I think if heat is an issue you need to look at better brake fluid.

Also what kind of rotor is this?

Remember when a brake pad contacts the rotors to generate friction(heat) the pad actually also generates gases these gases build up under the pad( think of it as a form of hydroplanning) all brake pads come with a slot or groove in the middle but it is not always enough to disapate the gases. Adding slots or hole drasticaly increases the gas disapation there by actually increasing surface contact for the pad.

Again i am not talking about F1 or Lemans or Indy. Most of those braking systems are worth more then our houses. But for general use and brake efficency slotted/ cross drilled are heads and tails above stock.

So are we sure about the gases, from what I read that was more of an issue with 50s brake pads that used asbestos and other things that created gasses and that it was not an issue as much any more.



Also here is some interesting information, not sure how reliable the company is though.
http://www.smothers.com/specials/powerstop.html

Also, and this is an assumption, I would think that the Hawk Pads have figured out what bonding agents release the most gas vs what they cost. If they are able to brake at higher temperatures then they have figured out a way to reduce the gas that is released at high speed braking.

http://auto.howstuffworks.com/auto-parts/brakes/brake-parts/brake-rotors1.htm
http://en.wikipedia.org/wiki/Brake_fade
http://en.wikipedia.org/wiki/Brake_fade


Some good info there. Also yes the gases have gone down but are still a factor in braking. It is no so much the off gas of the material but heat generated gases these days. Plus brake dust.

Cool thanks Stephen

Ive used the rotors from that company in TO aswell. Even in my Saturn days. And Ive glazed up a few stock brakes.. but I dont think Ive ever glazed my drilled rotors. So ya they do work better. But... Ive never seen anyone have rotors fall apart cause they were drilled.

They say slotted rotors will go thru pads way quicker the drilled rotors.

a friend of mine had expensive crossed drilled rotors on his turbo thunder bird and the front passenger side burst into pieces on the highway ruining his rim brake line and putting a nice hole in his fender. yes he was kinda hard on the brakes but never raced the car. its a tough call so why not just ditch the crossed drilled and settle for a slotted rotor, why go drilled when slotted is MORE then enough for aggressive breaking.

the difference between slotted and crossed drilled is 'RICE'

m.... no... the differance in slotted and drilled. is cost and effeciancy. Slotted are more expensive.. well more expensive then the Canadian brand I buy. Andg thru pads faster. so the drilled rotors will save money in the long run.

Altho putting drilled rotors or slotted rotors on a car that never sees a track is rice.

Mind you.. i can feal my brakes slipping in my envoy after a long drive with the camper or the car hauler. I may get some drilled rotors for it.

I have never seen a cross drilled explode either and i know alot of retarded honda drivers. Although i do believe they are weakened by the drilling, but if you compare them to stock the braking is much better. Everytime i drove my Integra to Montreal and had to all of a sudden stop for some idiot watching the grass grow outside Kingston my rotors warped. Switched to cross drills stop on a dime flipped the fuckerthe bird and never machined them again. Would i go rally racing with them....No. everyday street fuckyeah.

As far as I know, that's the only kind there is.

When it comes to brakes you often (not always) get what you pay for.
The theory works if their bult to work with the theory. Cheap cross drilled will often have hot spots at those points of drilling once on the car and they cause problems.

Drilled or slotted rotors won't do crap for you if there stock sized.

When you get into racing applications drilled is better, Slotted doesn't do anything.

I didn't read most of this thread, but the majority of the time drilled &/or slotted are basically to make it look pretty nowadays.

At one time, both helped to de-gas between the rotor & the pad, with the materials they currently use in brake pads, this is typically no longer an issue. Cross drilling was typically done to reduce weight, good I guess if your rotors are short term use, but they are more likely to develop cracks, especially if it isn't done correctly. While reducing weight may seem like a good thing, it also means you have less mass to absorbe/dissapate heat, which under severe braking can be a bad thing.

Both cross drilling & slots will wear your pads slightly quicker vs a blank rotor. For most, a blank rotor will be the best option. If you don't like a blank rotor, get the slotted. As far as actual braking performance is concerned, there won't be a difference.