I have always thought that you use slotted rotors for "scraping" the pads to reduce fade and cross drilling was for heat dissapation.

That comment earlier about them having less mass to absorb heat is correct but that is a good thing in this case because you have a larger suface area and less heat capacity which means more effective dissapation.

In my opinion cross drilling is a wank! slotting has a real purpose but it is debatable as to whether cross drilling's marginal advantages outweigh it's disadvantages (ie: disk cracking).

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for engineering purposes your brakes need to be able to cope with the extra weight in your car... not extra power..

road laws only allow a top speed of 110kph (in victoria anyway), so as long as your brakes can stop your 8-900 odd kg datto from that speed your fine... whether it has 100hp or 1000hp.

my engineer recomended 120y disks for my ute... i used stanza's

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street pads melt like butter on the track!!!

I saw a 12 sec CA18DET equipped ute a few months back and was shocked to see that it had non boosted stanza brakes on the front (R31 on the back) But apparently it passed the RTA test with flying colours.

Drilling is to let out the gasses that build up on the pad surface, it's common for rotors to get heat cracks around the holes,
slots do a simular thing, without the heat cracks, another benifit of the slots it to wipe the surface of the pads(machine) so the intentin is that they stay flatter and keep the surface clean, but with a reduced pad life, ( I read approx 10%)

I have neither cross drilling or slotting in my rotors in my race car. What looks cool is very big brakes.... slotting and cross drilling comprimises the strength of the rotors...may look sexy but I wouldnt bother...if your brakes are being used in a way they are continually overheating the only solution is greater diameter rotors and calipers to suit. I used standard stanza slotted discs on the 1200 coupe race car and never NEVER had a problem with fade. I did however go through a set of pads every race meet or practice day. I could live with that as they were only $30 a set. Why have I got got Willwoods now??? good question because the car I bought came with them.
I would say for the street you wouldnt need to go bigger than stanza even with a CA18DET...you just wouldnt hammer them like you do on a track.

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The primary of cross-drilling or slotting your rotors is to keep the pad's from glazing over when run at high temp conditions (ie/ at the track), thus maintaining braking performance.

Yes, it will decrease the life of your pads.

I wouldn't bother with it unless you're seriously considering racing or really want the pose factor........ They DO look cool .

I can't tell you for sure whether it's better or not but from a similar disscussion on another forum I'm a member of I found this intersting little fact out. It has the benefit of always keeping the rotor clean of crud and stuff at the expense of shortening the lifespan of you're brakepads and rotors.


Does anyone agree with this this info I've heard?

Its decreasing the material into which heat can absorb, but its increasing the surface area of same material so as to dissapate heat better.

Its decreasing the unsprung weight whilst increasing the likelyhood of fractures appearing in the disc.

Porsches have them and they look cool.

gday thought id ask for your experience n whether you think drilling your brake rotors has any benefits? would it increase stopping power?