How much miles do you guys get with OEM pads on the track?!

 

OEM pads? 3 brake zones.

 

200 on-track miles with a race pad is going to produce heat-checks (veins). That's just the way it is with or without holes. The main reason people don't use drilled rotors for track use in an S2000 is twofold:

1) They are expensive and not readily available.
2) The small pad area of the S2000 caliper is going to destroy them.

Smaller pad = more pressure = more heat. With a large 4 Piston brembo you've got a giant pad which results in lower pressure and the heat disbursed over a wider area. The master cylinder produces a force which drives the caliper piston outward toward the rotor. Pressure is a function of the force applied over the area of the pad (P = F/A).

The reason holes are drilled in rotors is several:

1) the holes channel away the dust produced by the pad. The dust reduces the friction between the ad and rotor (like walking on marbles) so getting rid of it is good. Rotors sometimes come with slots to achieve the same effect.

2) the holes reduce the weight of the rotor (less mass) which is good. The rotors on the S2000 are unsprung so getting rid of it is encouraged.

3) the holes increase exposed surface area thus induce greater dissipation of heat to the air. Aerodynamically speaking I doubt this has any real effect but theoretically it makes sense.

The problems with swapping your flat, solid disks for drilled ones are also several:

1) holes reduce surface area thus increase pressure (P = F/A) which increases the heat generated which in turn causes the rotors to wear faster and possibly crack.

2) holes reduce the dust thus increasing friction and therefore increase heat (see above)

3) holes reduce mass meaning there is less rotor to absorb the heat which increases the temperature of the rotor and... (see above)

Unlike others I don't think drilled rotors are bad nor useless nor do I think they are in themselves bling. I do think however that changing your "normal" rotors for drilled ones overlooks the basic physical facts I note above. When used in a complete system designed for it they can offer excellent performance and durability. Simply replacing that single component of the brake system without making similar adjustments in the other components to compensate is just asking for a headache.

People look at a 996 and say "look. Porsche uses a drilled rotor so they must be good" overlooking and giant 4 piston brembo caliper in the process. The stock S2000 brakes are not designed for a drilled rotor. If you want a drilled rotor you need a brake system designed for it. You can't add them as an after thought (well you can but that's your problem).

 

3?? Damn man, push the pedal!

 

holes are only put in rotors for looks.

pcars only have them because owners think they look good. not because they work better.

 

[QUOTE=krazik,Apr 5 2005, 07:30 AM] holes are only put in rotors for looks.

pcars only have them because owners think they look good.

 

e=mc(holes in brake rotors are retarded)^3

edit: forgot ""

 

I understood that one of the function of the holes is to better release the gasses (dust too?) generated, but that this is also accomplished by cutting grooves in the pads (like most manufacturers do), yet it wont weaken the rotor. Decrease in surface contact applies to both. An ex-professional bike racer told me it was routine for his support team to cutt grooves in new pads.

 

My pads come with a single groove. I'm thinking about trying to cut a few more in the next new set I buy, in order to try and ease the break-in process. I like those Panther+ pads pretty well, but they do seem to suffer from pretty severe outgassing problems the first time they are used hard. No issues after that.

 

modern pads don't outgas significantly, if at all. 25 years ago the holes in the rotors did something.

The cut in the pad is for better bite.

Slots when designed right can offer better brake bite.