groved discs

[Mr RSi]

is there any point in buying groved front discs ? do they make braking any better ?

 

[Jamie]

no not really, just maintains optimum tempatures for braking by cooling, but the calipers max out way before the discs constrain you

 

[GordonD]

Drilling and slotting brake disks was done originally to improve the "bite" of the brakes. Any dust or crap under the pad would prevent all its area pressing against the disk, and so did the gas the comes out of the pad as it heats up. The gas and the dust and whatever else would quickly get wiped off and escape through the slots or holes. Modern pads don't have the same problem of outgassing.

So there is still some benefit in bite. But the slots or holes will wear the pad faster, and with holes and/or slots in it the disk has less mass and so will heat up faster, and it is more likely to structurally fail under high physical and thermal loads. A disk designed for the holes and slots will be OK, but it'll cost more, and standard disk that's been slotted or drilled will be more likely to fail earlier.

Slotted and drilled disks are like a lot of car modifications things that young men spend their money on by convincing themselves they must work better because that's what racing cars use, they look good. If you want your car to look good and you are happy to spend the money, do it. Just don't expect the brakes to work any better, or to last as long unless you buy really good ones.

 

[Andy]

My understanding was that grooved and dimpled was the way ahead.

Indeed I've beasted a car with OEM discs and then again with aftermarket discs. At normal, legal, road speeds there is no difference. From 80 if was like throwing an anchor out of the window.

 

[team_penetrator]

Drilling and slotting brake disks was done originally to improve the "bite" of the brakes. Any dust or crap under the pad would prevent all its area pressing against the disk, and so did the gas the comes out of the pad as it heats up. The gas and the dust and whatever else would quickly get wiped off and escape through the slots or holes. Modern pads don't have the same problem of outgassing.

So there is still some benefit in bite. But the slots or holes will wear the pad faster, and with holes and/or slots in it the disk has less mass and so will heat up faster, and it is more likely to structurally fail under high physical and thermal loads. A disk designed for the holes and slots will be OK, but it'll cost more, and standard disk that's been slotted or drilled will be more likely to fail earlier.

Slotted and drilled disks are like a lot of car modifications things that young men spend their money on by convincing themselves they must work better because that's what racing cars use, they look good. If you want your car to look good and you are happy to spend the money, do it. Just don't expect the brakes to work any better, or to last as long unless you buy really good ones.

Exactly right...

 

[Neil G]

I've had them on previous cars and TBH didn't notice much difference....TbH the EBC ones I had made the brakes worse.

Seems the grooves/slots just fill up with c**p which quickly corrode the disc.

 

[Andy_J]

So there is still some benefit in bite. But the slots or holes will wear the pad faster, and with holes and/or slots in it the disk has less mass and so will heat up faster,

more surface area tho so will also cool down quicker!