Does it make a diff? because i see all the really nice cars like the s500 come with them, i hear 2 things commonly about it.
it cools down faster
but you lose breaking power due to the less surface area..
they both sound reasonable.. what do you guys know about this?

 

the holes are to take in dirt so that pad vs surface contact is as clean as possible. The lines, material and a buncha other stuff are to preven overheating=break failure. But other than that, having larger rotors and cooler breaking systems is just a fancier way to slow down for a light or a turn.

Breaking distance is still the same since it all depends on the wheel's road friction...you can slam on either break and skid, or you can break just hard enough on either to slow down fast and not skid.

Oh, they do look much better....whiptidoo...spray paint them.

 

there's slightly more to it than that though. the holes also allow for greater water shedding in wet conditions and slotting does allow for escape of gasses that build up around the pad during heavy braking (this is also a form of heat dissipation like etxxz said). technically yes you are losing some surface area, but not a great amount. and it *will* help your car stop faster. true, road friction plays alot on whether you will begin sliding, but overall pad/rotor friction is what's going to slow down the vehicle. brakes lose their integrity when they heat up. this keeps them cool and allows them to work more efficiently. i have seen firsthand the difference on going from standard to slotted/drilled rotors on sports cars. we did it to my friends TT 300ZX and it stopped a hell of alot faster.

it is a true statement though that Acura did it to eliminate heat warping on the TL without having to modify the calipers/spindles/rotor setup.

SSTS

 

One of the disadvantages to cross-drilled rotors is that under heavy abusive usage (racing etc..) the cross drilling weakens the metal structure and they have been known to be prone to stress cracking. There are 'dimple drilled' rotors for the TL available that have holes drilled on both sides, but not all the way through. They have the advantage of cooling and water/gas shedding, but maintain their strength integrity. I think this is an excellent compromise between full cross drilled racing rotors and OEM slab rotors. I have dimpled drilled & slotted rotors on my TL and they really perform. Very smooth. and I can feel a big difference in the lack of fade under repeated hard stops.

 

For street riding cross drilling is overkill.

For 2 hours on the track, they are probably a must

 

yeah this is true about the cross drilling. chamfering the edges during drilling though prevents this problem by changing the stress distribution during expansion. a good company will do this to their product, and properly done there should be no integrity compromise. alot of companies don't however. FYI.

i wouldn't call it 'overkill'. mainly because normal driving resulted in warped rotors to begin with for the TL. granted the rotors may have been pretty crappy, but that i wouldn't know. i will personally say though that if you live in wet climates or if you drive in alot of stop/go traffic or highway traffic, a few extra feet you save on braking distance may just save your ass. but for the cost and use, most people will do just fine with normal rotors. i agree on that. now if you had people who just drive to work every day going out and getting brembos, well then i would say it's overkill.

 

It all has to do with the driver. Cross-drilled rotors and brembo brakes will do you jack squat if you're talking on your cell phone, drinking a soda, and staring at the hot chick in the next lane, while not paying attention to the road. Also, cross-drilling will do you no good if you don't know how to brake as well. Most people never fully utilize their braking power anyways, even in emergency situations. Also many people still don't know how to brake if they have ABS. So yeah, these fancy schmany brake technology is a must on the track, but you're not on the track 90+% of the time. Most of the time, you're stuck in traffic, where the only thing cross-drills are good for is showing off how much money you wasted trying to impress the 10% of the other drivers out there that will actually notice you have cross-drills.

 

and
I hate it when that happens.... :o