Brake Discs - Drilled / Slotted

[ninjag]

Apologies if this has been done to death, but I had a search and nothing recent stood out and I guess opinions can change over time.

I've got drilled vented discs on the front and regular vented on the rear and I think the drilled discs are what's causing a quiet but noticeable noise when driving with the window down at low speeds.

Are drilled/slotted discs really worth it for public road driving? I'm sure I read or watched a test which showed no improvement in brake performance until you reached heat fade territory where they would then excel, but I probably never get them hot enough to worry about this. I'm sure I read that they will eat through pads faster - does that not imply they work better from the offset though and there's also the noise they make all the time when driving at slower speeds. 

[Flint123]

I think drilled discs have a "cool/I'm a racer" look about them (which I've done myself in the past 😱) but I don't really think there is any need for them day to day on the road.

I've never noticed any noise issue, but I agree that they tend to go thru' the pads quicker.

All IMHO of course.

Ian.

[Stevey Y]

Hi, recently fitted drilled discs to the front of my Audi and they definitely make a difference in heavy rain I do about seven hundred miles a week [cab] a lot of it around town and the difference is that the standard braking used to take subtly longer in heavy rain to stop which normally manifested itself as slowing with a sudden grab at the end of the process, the drilled discs have eliminated this as the braking is controlled and progressive right up to the stop with less pedal pressure.

I have used grooved discs before and to be honest the pad wear and noise are not really acceptable, if you look at a lot of the Mercedes and BMW sportier models  including Porsche they use drilled only discs which with their testing regimes sort of gives you a clue as to what is the most effective option.

Steve.

[ninjag]

Interesting, wet performance never crossed my mind, now I have something to think about. Thanks.

The noise is difficult to describe, but I'm sure it's the drilled discs. I'll keep my eye on it though.

[ninjag]

Just to follow up on the noise from my wheels it is a little like the noise when free wheeling on a bycycle. It sounds the same on both sides as well.

[Stevey Y]

21 hours ago, ninjag said:

Just to follow up on the noise from my wheels it is a little like the noise when free wheeling on a bycycle. It sounds the same on both sides as well.

Hi sorry for the late reply but I have not been able to sign in for two days, strange, anyway from your description I would say if the pads have done a lot of town work over the last couple of years if there is still plenty of wear left in them it may just be as simple as taking the pads out and giving the stainless runners a good clean and regrease as it sounds like the pads are not quite releasing properly.

Steve.

 

[ninjag]

7 hours ago, Stevey Y said:

Hi sorry for the late reply but I have not been able to sign in for two days, strange, anyway from your description I would say if the pads have done a lot of town work over the last couple of years if there is still plenty of wear left in them it may just be as simple as taking the pads out and giving the stainless runners a good clean and regrease as it sounds like the pads are not quite releasing properly.

Steve.

 

Thanks, I'll add that onto my growing to do list!