Those Brembos, fixed caliper? Or not? [Patent inside!]

[Farred]

this has been my idea on slotted and cross drilled rotors for years.

http://www.rx7club.com/showthread.php?t=480082

"More facts about rotors. May the great myth of drilling rotors for improved cooling finally die...

Darrick Dong; Director of Motorsports at Performance Friction.

"In the days of asbestos pads there was a gas boundary layer that appeared at the interface area of the pad and rotor. Although that gas boundary layer still occurs it is much less of a problem with modern friction materials. Slots are more than adequate to carry that gas away. Years ago that gas boundary, along with reducing weight, led to the popularity of drilled rotors. However, in the intervening period, the myth has persisted that cooling is the main reason for drilled rotors. Anyone that tells you that drilling makes the disc run cooler is smoking crack."

Why is Dong so adamant? Because he works with racing brake systems for a living and it isn't too hard to take two identical rotors, drill one of them and slot the other, put them on a brake dyno and measure temps and life.
More facts about rotors. May the great myth of drilling rotors for improved cooling finally die...

Darrick Dong; Director of Motorsports at Performance Friction."

also doesnt cross drilled reduce the amount of surface area for the rotor?

[Matador]

All the arguing over something Trivial, and nobofy notices those MAD coilovers or the brake cooling ducting.... smh @ u guys.

[Nurburgring]

Matador, it is unfortunate but we should actually expect the "FT86 scene" to be full of hellaflush/stance/jdm retards and posers. Nothing new there.


Drilled rotors for a race car? you guys have certainly swallowed the marketing bullshit all the way through. They belong to show and drift cars, real racing cars will always use plain or slotted; drilled tends to fracture in the area surrounding the holes.



This in an actual Toyota F1 car brakes:




This is the Audi R10 LeMans winner brakes:





These are NASCAR brakes:








And this is what happens to your typical aftermarket drilled rotor in a race enviroment:

[Farred]

ed zachary

[Dave-ROR]

Originally Posted by Slide

Lol this from a guy who has a race preped car... Says slotted/drilled discs are for show wow...

Its really hard to find road race cars with drilled rotors and it's for good reason. Slotted and drilling (on the road, slotted does have some benefits off road) fixes a problem that hasnt existed in what 40-50 years now? Pad off-gassing is no longer an issue with modern brake pads. Drilling rotors makes them weaker. Rotors cast with the holes are stronger but all suffer from having less mass. Less mass means less heat holding capabilities. That in turn means less heat is taken out of the cars braking system (pads, calipers and fluid). You also have less friction area as the pad doesn't create friction against air.

To make a modern analogy take a computer CPU and think of it as the caliper assembly and think of the heat sink as the rotor. Do you want a small heatsink with an uneven mating surface (slotted/drilled) or a nice large smooth surface?

On a street car you are less likely to see any problems (the worst I've seen is extensive cracking) but on the track you'll see them break sometimes (not often but I've seen it twice in person, one of which resulted in a NSX slamming into a wall at Sebring).

On the show side people think they look cool so they end up on expensive street cars because most people who buy those cars want that. Every Porsche race car (factory and independant) that I've seen in person have blank rotors yet every (or most?) street p-cars come with drilled.... (cast that way)

[Dave-ROR]

Originally Posted by MatadorRacing_F1

All the arguing over something Trivial, and nobofy notices those MAD coilovers or the brake cooling ducting.... smh @ u guys.

Lol yesterday I tried to zoom and read the numbers on the spring to figure out the rate but I failed. I like the ducts (and did see them) but they must have another piece to bring the air closer to th caliper or center of the rotor.

Beyond them looking pretty they don't help any if us much

[70NYD]

Slotting it reduces the surface area as well. Drilling it leads to a weaker rotor than a slotted, but in reality, ideally, drilled rotors should be done so in a certain manner, for best gas extraction I won't go in to it cus there is no point, but on paper, drilled removes brake gas buildup faster.

[NESW20]

Nurburgring and Dave - thank you for taking the time to explain that so I didn't have to. I don't know how many times I've advocated for blank rotors and everyone tries to argue. We don't have to worry, though. Toyota won't put anything other than blanks on the FT.

[NESW20]

I wonder if they'll offer the air jack setup as an option..........

[Dave-ROR]

Originally Posted by NESW20

I wonder if they'll offer the air jack setup as an option..........

I'd buy that option in a heartbeat!!

[czar07]

yeh porsche must be doing it wrong with the best braking car in the world hey? factory "drilled" rotors arent actually drilled, they are cast like that. its not for better cooling its for weight reduction.

[Spaceywilly]

pretty sure it is fixed... definitely funky looking though

[Dave-ROR]

Originally Posted by czar07

yeh porsche must be doing it wrong with the best braking car in the world hey? factory "drilled" rotors arent actually drilled, they are cast like that. its not for better cooling its for weight reduction.

I already addressed why porsche sells "drilled" (and mentioned rotors cast with holes) and pointed out that they RACE with blanks.

[ichitaka05]

Originally Posted by czar07

yeh porsche must be doing it wrong with the best braking car in the world hey? factory "drilled" rotors arent actually drilled, they are cast like that. its not for better cooling its for weight reduction.

Supra (MkIV) had shortest braking for longer time than Porsche (til '04) and Supra had a plain rotor