HyundaiKitCoupe

I'm not one to talk but I will back dtn here and say my stockers warped quick daily driven to the ground, about 40 miles per day with red light traffic. I still have majiks rotorpros which are about the same price if not a few $ more than stock, drilled and slotted. Pad life was 4 years daily driven in the worst traffic and tjose pads werent even ceramic. I put about 30,000 miles on those before it was time to change. Fourth year with rotorpros and not a sign of ripples.

Braking/stopping power is less, less grip. But there is less wear compared to stock. But better grip toward the end of padlife compared to stock. All in all i tjink you get more brake throughout the whole life of the pad with drilled/slotted.

Dont forget f1 cars probably use regular rotors because they want the most stopping power for one race, not four years. They dont care about keeping used rotors, so there is no comparison.

Drilled holes do keep pads and rotors cooler. Cheap rotors will crack, but rotors being cheap is a new topic. I think its a huge debate that would have to be answered by real engineers who specialize on the subject and are up to date with technology and not refer to other forums. Anybody wants, I'm meeting up with a Ferrari engineer this summer and can swing him this question.

AGreen

You made me do it......

'Scuse me while I whip this out!!

side 1
side 2

Listen kewlkat, like I already said, it's not about increasing the surface area of friction. Yeah, it decreases the surface area of friction. But you're not drilling holes and machining slots because you want to increase the surface area of friction, you're increasing the surface area of the whole rotor. That means there's more metal exposed to air for better cooling capacity. You're cooling the brakes down to prevent what's known as brake fade. It's all about the heat dissipation. Let me scan this for you from a text book.






The gas "theory" isn't a theory. It's fact. It says that Gas fade is very rare because it's true. In everyday life, people don't race their cars. On the track, it's more common because they demand a hell of alot more of their brake systems.

SR Tech

Got that same book.

Pascoile

As far as I know, for someone who gets on a race track once in a while during summer, drilled/slotted rotors are the last thing you want on your car.

Here's my Snyper drilled/slotted rotors brands new.




I drove on the street with those for 1 year no problems, but here they are after my first lapping day last summer.






So then I decided to try plain disk, here's the result after 2 months.




So for the next set I tryed something else, slotted only.



They endend up just like the others after 2 months, cracked in 3 different places.

These are quality 11" cast iron disk, not the cheap recycled stuff from China most rotors are produced with. In addition I fabricated myself some brake cooling ducks with 3" aluminium dryer hose and I'm only using Hawk Hp+ ferro carbon pads, which are entery level racing pads, not the most hardcore pads out there available for my application. I have this problems with disk craking only in the front, where most of the braking is all done anyways.

All that just to say: for the street, drilled, slotted, drilled/slotted or just plain rotors, pretty much anything is going to do the trick. On the race track, drilled aren't recommended, slotted are to prevent brake fade, but be carefull of the size of the slots. Just plain are most likely to warp quicker. A good idea could be to have the rotors frozen cryogenicly, I haven't tried this option yet, but will soon. wink1.gif

optimoprime

wow this is all great info guys, keep it coming

01tibby

dont know if this was covered, but bigger rotors dont necessarily have more surface area, just a greater moment of inertia, which makes it easier to stop 300+ sticky as all hell tires.

pascoile, you should try sizing some wilwood rotors with wilwood rotor hats to match your calipers. the hats are expensive, but the rotors can be had for very cheap.

tdonnell

Damn pascoile, you must beat the hell out of your brakes!!

Try getting the 12" rotors from the xg 350, I stop damn hard with them and have had no issues for over 6 months, not even the smallest hairline crack.

Although I don't think you can get aluminum calipers over them, you would have to use the cast 2 pistons that are heavy as hell.

Just a suggestion anyway.

tib _500

a very interesting discussion. Pascoile have you tried using rims that will directing air into your braking system(such corvette rims). http://www.joby.se/corvette/div/corv...els/91zr1.jpeg basically like picture just slots on rim directing air to rotors and such, which i think is done just by switching the wheels to other side. also " where most of the braking is all done anyways" isn't braking mainly on the inner side where pressure of the piston/Piston's are applied(still pressure on outside but caused by the pressure of inner)? working in a shop i typically see inner pads wearing slightly faster than the outer(in both cross dilled what not and OEM).

also to add to this in Ferrari's and other exclusive vehicles, isn't there a brake cooling system integrated to suite having cross drilled/slotted/ whatever. I'm pretty sure they have air vents directing air to the brakes.

KeWLKaT

Sweet! Good to see the discussion is still going and remains interesting! I love reading this stuff guys, keep it coming!

Pascoile... interesting info! Why do you think everything is cracking? Perhaps it keeps overheating?

demon_fox

wow alll this over rotors