An article on brake myths

[lewd lude lover]

Really? Oh for shame Nathan. Go on, treat yourself.

[NafemanNathan]

What's the point mate? How can I (Or anyone for that matter) compete with the mind/opinion that is LLL's?

[Donald]

Introducing big, evenly spaced holes just gives the metal more wiggle room to flex on its own as its temperature changes unevenly to the metal around it. Drilling holes means less surface tension to combat this issue.

I've not read it but going off of this little segment, Nafe, I don't think I'll bother

[lewd lude lover]

What's the point mate? How can I (Or anyone for that matter) compete with the mind/opinion that is LLL's?

Well, to be honest I'm not sure. Many have tried and failed . Donald seems to be able to do just fine but he is a rare and special flower. Rare and special.

[NafemanNathan]

Introducing big, evenly spaced holes just gives the metal more wiggle room to flex on its own as its temperature changes unevenly to the metal around it. Drilling holes means less surface tension to combat this issue.

I've not read it but going off of this little segment, Nafe, I don't think I'll bother

But please edit that so it doesn't look like it's something I actually wrote

[NafemanNathan]

Many have tried and failed .

Again, in your mind/opinion

[lewd lude lover]

Ok, maybe if I rephrase it you can better understand my proposal. Just sitting there whistling is nosh.

All/most available information, available to us that is, on drilled brakes says no real benefit can be found and its mostly a hangover from old tech and it looks good. For our amature understanding the addition of holes in the disc offers only shorter disc life and a rakish look to the car. In most cases its a choice of the style you want to go for, rather than any known braking aid provided, with todays materials.

Now consider that list of yours. That has to be the top 7 list of under used motors on the planet. Not one out of 100 of them will ever be half pushed to its potential due to being owned by factory owners from hull who go to the golfcourse in it to show off or stashed in a garage on show to the owner. Yet they all have this holes in the disc look to them... Again for reasons we cant really put our finger on. Can we? Carbon ceramic discs are somehow a step back and now need holes again? I dont think so but I dont know. Educate me.

Now, car producers are all for making a nice car but at the end of the day all they really want is a nice big house and the kids in a good school like anyone else and making expensive cars gets them that fast. Making those cars fit the idea of a fast expensive car is half the battle and thats where the marketing dept comes in. If everyone else has them and you dont and yours looks more like a normal car in comparison tell me what would go on in that board meeting..

Can you tell me why all these car producers have holes in their discs? Tell me why they have all got them but we understand them to be next to pointless and I will accept that it is not simply styling. Otherwise its just more equipment and work to produce something that has no positive effect to the mechanics of the situation. Thats called cosmetics... and is marketing.
imho.

[NafemanNathan]

imho.

Believe me when I say we know it's in your honest opinion!

I'm sorry, but I don't buy this conspiracy theory of yours. Yes cheap drilled discs crack when used under intense conditions, but that's because they're immitation, using cheap materials and manufacturing making them more affordable to the general population. A properly engineered drilled brake disc where the drilled holes are strategically placed between the cooling fins, not too close together and have a radiused run out so as not to weaken the structure with allow the disc to cool efficiently and allow water, debris and gases to escape making for better braking in all conditions.

Most brake pads these days have a groove or two through them in order to aid in the escape of water, debris and gases, but this is potentially one groove that will just get blocked up. I have personal experience of removing/inspecting numerous pads where said groove has been blocked up with crap. And generally the reason for me inspecting the pads is because I've been experiencing brake fade. This is when they've been used in conjunction with plain discs.

Now I used to run a set of Tarox sport discs. These retail at £300 a set (Don't worry, I didn't pay anywhere near that much for them... Of course ). (Edit: These are drilled and slotted, but not overly). I can guarantee I've done my heaviest driving whilst my car was sporting those discs. Not once did I experience brake fade. In fact I intend to have them re-drilled to fit the 5th gen because they gave me that extra reassurance that I could stop when I wanted to. I can also guarantee there are no signs of deterioration on them, only general wear.

Of course you're going to say, but that's in a 200bhp car so hardly pushing it. But then I can say, but those are only a £300 pair of discs and I could probably pay three times that for discs if I had a car that had three times as much power to warrant them... And I would, because again, they'll be a more superior disc.

So my conclusion is anything done poorly/cheaply can break, and there are levels and limitations to every next level of engineering, just pick the right one for your needs and ability... IMPE

And I'm sorry, I'm not going to entertain the whole "because marketing told them to", because their customers are gullable mugs. If they were that gullable the manufactures would be able to buy in cheaper plain discs and market them as the same as F1 brakes, job done!

There... that answered enough for you?

[wurlycorner]

Can you tell me why all these car producers have holes in their discs? Tell me why they have all got them but we understand them to be next to pointless and I will accept that it is not simply styling.

Nope, none of us can't say for sure, because we're not the people responsible for the design of that particular package. But my post did set out, based on engineering principles, why they might be there for valid reasons.

Carbon ceramic discs are somehow a step back and now need holes again? I dont think so but I dont know. Educate me.

Not a step back, no (although that depends on application...*) but they'll have different characteristics than steel discs, i.e. crack propagation will be completely different, they do run at a much higher temperature just in order to work (so might have less upper heat capacity spare and therefore need more cooling potential etc.) they have different wear/disintegration characteristics (e.g. generate a lot more dust than steel) will have different gassing properties etc. All reasons why including holes might be needed/beneficial.

Basically as I said, there's no such thing on this as 'one right answer'. It will vary from package to package and application to application.

And yes, 'styling' might also be part of that (but it sure as jobby won't be the biggest part on something as functional and safety related as brakes).


*e.g. it would be a step back to fit ceramic brakes to a fiesta, because it would cost too much and the car would just spend all its time running into the back of the car in front because they never got hot enough to actually work!

NB: this isn't a 'get James' thread or a 'James has got me riled' thread the posts are about offering information and trying to answer your question

[lewd lude lover]

Amazing. thank you. That is a great reply. I have learned something and thank you for it.

Just a couple of sentences of that rather than the folded arms and whistle would have achieved the same thing but either way its good information and I value it.


I still feel the jury is out as far as the actual effectivity of them but I concede fake v 'real' as a big factor.

@wurly: I wonder if the new materials do outgass etc? Maybe it has gone full circle?