AJL0365

Hey I'm purchasing a set of new Rotors for my 02 GS300 and was thinking about Brembo because Im starting to mod my car a little bit. What is the Difference between Slotted and Cross Driller Rotors besides the look? Is one better than the other like it shops quicker?
Thank You

rominl

iTrader: (4)

no, both of them do not help stopping distance. if anything, it's more about brake fading. they are supposed to help cool down the rotors faster.

but in real world, imho, they are more for look

AJL0365

oh okay, thank you
So ya think Lexus could have just put simple regular but larger rotors instead of the Brembo Brakes in the IS-F? I always thought they did something special. Guess you learn something new everyday!

Thank You!

rominl

iTrader: (4)

i think you are missing the point. they can always put larger brakes, that will increase braking power, but at the same time can seriously throw out the brake balance, which is the key in braking.

keep in mind larger doesn't always mean better

and all performance brakes they are all drilled/slotted for cooling purpose. it's needed otherwise in track use situation, after couple of laps and the car will have no brakes at all

AJL0365

Oh okay! Thank You!
Ordered a set of Brembo CrossDriller rotors, Hopefully I will like em'

kt22cliff

You do not want to have drilled rotors in race situation. It will be more likely to get cracks on the rotor if you use drilled rotors in race situation. Stick with slotted.

Of course on street, it won't make much difference, whether you have drilled slotted or blank rotors besides looks.

rominl

iTrader: (4)

ap racing are drilled. brembo are drilled. they are used extensively in racing?

or you mean aftermarket drilling?

kt22cliff

The drilled ones are for street application. AP and brembo sell drilled rotors b/c they can charge people extra for it. Go to a racetrack for SCCA or NASA race days and look how many of them have drilled rotors. I've seen people who brought their street car with bling bling brembo drilled rotors to HPDE and crack them right on the track after two 20 minute sessions.

rominl

iTrader: (4)

that's interesting, didn't know about that.

mitsuguy

iTrader: (2)

I can vouch for that, in an entirely separate situation / place... had a good friend lose his brakes completely at 110 due to a broken rotor... (two pieces)

since then he has always gone back to a stock like rotor...

the only real good cross drilled rotors are the ones that have the holes cast in them to start - the metal grains are organized differently when the holes are cast in place vs being just drilled... Porsche rotors come to mind...

rominl

iTrader: (4)

porsche brakes are made by brembo. and i would tend to think brembo GT brakes, their rotors are cast with the holes already there if anything. does that mean they are ok? according to kt22cliff they are not?

and that's why i asked in #7 if he's talking about aftermarket drilling. if so, they are bad for sure. in fact, for stock replacement, brembo never has drilled ones as far as i know, it's just brembo blanks. it's aftermarket companies putting the holes. and personally i never recommend that

and in that subject, i will go back to kt22cliff. when you said "their street car with bling bling brembo drilled rotors", you meant stock brake setup but with stock replacement brembo drilled? or you meant any of the brembo full GT bbk as well? if it's the first case, then yes i totally agree. it's the 2nd case that i am a bit reserved about

mitsuguy

iTrader: (2)

I believe he was talking about, and I as well, those blanks that have been drilled by a third party... one good reason they don't work well, more than anything, is that in stock sized replacements, the original rotors were sized for good heat dissipation and enough mass to retain a good amount of heat energy... now, take the same size rotor, decrease its mass by 5-10% and use it in an extremely demanding way, and you get rotors that are severely overheated and prone to cracking...

kt22cliff

No when I said bling bling brembo drilled rotors I meant authentic brembos, OEM and aftermarket. In fact the worst I've seen was in porsche OEM brembo drilled rotors from 997 crack and ruin the guy's wheel and whole front right side of the car at Limerock. I saw what's left of that front right rotor and about 1/3 of his rotor was missing. I've seen many people with aftermarket Brembo GT bbk with drilled rotors on their BMW's - mainly b/c I've done more BMWCCA events than anything else and some PCA events - either crack them outright or not being able to do afternoon sessions b/c there were cracks that developed hole to hole after the morning session where it would not be safe for them to be on track.

rominl

iTrader: (4)

wow really, that's very interesting info, great stuff!

ivanj

I know this is an old thread but when I used to garage wrench for a fellow who, when he raced his Corvette he used drilled rotors. He would then throw away the drilled rotors after each race. He said they would warp and crack if used for more than one race. Then he would put the stock rotors back on, I forget what they were, and I would help. He also changed the brake fluid after every race.

He was a materials aerospace scientist/engineer who helped design composites for military aircraft.

I myself use slotted vaned brakes for the street on all our vehicles that have the black corrosion-resistant hats.

BTW
It is remarkable how many stock calipers are made by ATE for Brembo and then badged AMG, Porsche, etc. Think about that before you buy aftermarket bling brakes....