"Ceramic" brake pads

[Avonvilla]

My understanding on brakes is that the disc no matter how big, slotted, cross drilled or whatever is only there to absorb heat, all the above just help cooling so it's all just to reduce break fade. On this theory and having never tracked the elan and suffered fade on the road and also with me being tight  :) i thought the standard discs would do at least until they "need" changing. I can say already that there a big improvement on stock pads, they bite straight away and the feel is differant too, cant wait to try them in anger  ;D

[Philbo]

[quote author=Avonvilla link=board=suspension;num=1094668951;start=15#20 date=01/05/05 at 16:19:09]My understanding on brakes is that the disc no matter how big, slotted, cross drilled or whatever is only there to absorb heat, all the above just help cooling so it's all just to reduce break fade. On this theory and having never tracked the elan and suffered fade on the road and also with me being tight  :) i thought the standard discs would do at least until they "need" changing. I can say already that there a big improvement on stock pads, they bite straight away and the feel is differant too, cant wait to try them in anger  ;D[/quote]<br><br>Not strictly true.<br><br>A big disc means that the place where the brake pad is applied is further away from the axis of rotation of the wheel. This means that the effort required to "grab" the disc is less. It also means that the disc is actually spinning faster further out than near the centre, though I can't work out if this is a good or a bad thing from a braking point of view.<br><br>But these pads do sound interesting, I might give them a go.

[Darren]

[quote author=Avonvilla link=board=suspension;num=1094668951;start=15#20 date=01/05/05 at 16:19:09]My understanding on brakes is that the disc no matter how big, slotted, cross drilled or whatever is only there to absorb heat, all the above just help cooling so it's all just to reduce break fade. On this theory and having never tracked the elan and suffered fade on the road and also with me being tight  :) i thought the standard discs would do at least until they "need" changing. I can say already that there a big improvement on stock pads, they bite straight away and the feel is differant too, cant wait to try them in anger  ;D[/quote]<br><br>I'm sure I read somewhere that the purpose of the groves in groved dics, was to help with the 'removal' of brake dust from the pad/disc surfaces. The groves also help to 'scrub' the pad surfaces and remove 'glazing'.<br><br>I can't really see how a 'surface' grove would 'aid' in the cooling of a cast iron disc. Especially given the fact that the disc is already vented to allow air to circulate between the 'two' disc surfaces. Cross drilled holes would allow air to circulate but I can't really see how a less than 2mm surface grove is going to aid cooling that much.<br><br>Just thinking out loud  ;).<br><br>Darren<br>~~~~

[philip_sloper]

[quote author=TStevens link=board=suspension;num=1094668951;start=15#17 date=01/05/05 at 02:29:48]<br><br>Redline Motorsport also stock these, as well as the Ferodo equiv (which is half the price) 01606 737500[/quote]<br><br>I would be wary of the Ferodo "equivalent" unless they can guarantee that the pad material is identical.

[Avonvilla]

Philbo - didn't mention that in the book i read  :) interesting though. I would guess that the further out the disc is ( ie bigger ) it moves quicker so in theory has less friction in the same place but it must all be very small differances ?<br><br>Darren - yeah i was told that too but dont pads glaze because they get too hot in the first place ? Not sure what that means  ??? Also i was told grooves help cooling in the same way as cross drilling does, apparantly the number of grooves and the angles of them is an exact science to get the brakes hot but not too hot. Would be very intersting to read a test of solid to slotted discs and the differances in a controlled enviroment.

[Avonvilla]

Found this<br><br>http://www.shotimes.com/brakes/part2.html<br><br>So it seems that with the newer pads and ceramic especially the only benefit of slotted rotors is reducing fade if your getting any.<br><br>Oh and of course there cheaper than Lotus originals !  :)<br><br>Oh and look better too !  ;D

[ESM]

Water is displaced more effectively with holes/grooves as well but since the braking torque before lock is reduced by the wet road anyway its of doubtful benefit. I would also imagine that the coefficient of friction will, effectively, be greater with a discontinuous surface since there will be hysteresis losses associated with the deformation of the pad material into and out of the gaps - can't be arsed to figure out how significant it might be though  ::)

[Sy V]

Good!<br><br>Because I can't be arsed to look up "hysteresis"!

[Game-on]

So your now talking to me...  ::)<br><br>Are these good or what !!!! LMAO<br><br>Game-on<br><br>Also what the hell is : hysteresis  :P<br>

[philip_sloper]

[quote author=Phil S. link=board=suspension;num=1094668951;start=0#0 date=09/08/04 at 11:42:31] These compounds are designed as a full competition pad, but due to a wide operating temperature both can be used successfully on the road but the best results will not be realised unless used on a race circuit....<br>...dependent on the temperatures achieved and level of performance required you may not see the full potential.<br><br>Paul Wilkinson<br>Competition Braking Products<br>[/quote]<br><br>Fade is usually caused by pads & discs getting too hot; my understanding from the above is that in road use the Pagid pads may not get hot enough to give max performance, as they are actually designed for competition use. So the cooling effect of slotted discs may not be of benefit with these pads.<br><br>However the other cause of braking problems is overheated brake fluid, and hot discs do transfer more heat to the fluid so if slotted discs run cooler that may help.<br><br>What really surprises me about the Pagid pads is how much better they are than Greenstuff when cold, given their competition background. I expected them to be superior when hot, but they also work brilliantly even when stone cold, unlike the Greenstuff that I had fitted before.

[Paul.P]

Totally agree with you Phil !

[davidjt]

Finally got so p*ssed off with my Greenstuff pads that I ordered the Pagid pads from Performance Braking.<br><br>Have to say they're the most helpful people I've come across in a long time. (They also explained that these aren't ceramic - just high performance racing (as in F3 & GT) material - which is probably covered in this thread already))<br><br>I'll be bedding  them in around Brands Club on the 19th, if  it's dry!   If it's raining, I won't be going fast enough.

[davidjt]

Verdict on the Pagid pads - the best upgrade I've made on the car since I bought it  (OK - with the exception of the Everest chip.  ;D)<br><br>Just as the chip transforms the power delivery, the Pagid pads give you the confidence to actually use the performance. The day itself was so-so: bloody cold, too many hooligans in EVOs and I've had 'flu all week, but at one point I was assuring the Instructor: " I really can stay off the brakes into Paddock much later than that!<br> ;D ;D ;D<br><br>Unless Bling is your thing, BUY THESE PADS AND SAVE YOURSELF A FORTUNE ON FANCY DISCS!

[Sy V]

So David<br><br>Am I right in assuming you've fitted Pagid "Blues" - Metallic Based RS4-2s?

[davidjt]

Sy, <br>Correct.  (In fact , if you look carefully, the bright blue is slightly blingy, in an understated, tasteful kind of way.)<br><br><br>Dico<br>Using stock (new) discs, Goodridge hoses and can't remember which fluid we finally settled on -  but I'll find out. On the road, they work straight away from cold (unlike you-know-what).<br>For serious track competition, big discs are probably the way to go, but for fast road use, occasional track days and hillclimbs (with the exception of Pike's Peak), I think these pads do the job: I expect journey times to come down a lot, as for the first time I have confidence in the middle  pedal and can feel what's going on.      <br><br>I could afford  Hi Spec, or even AP if I wanted to; I love the car, have ordered an 'Indiana' hard-top, and have a re-spray in mind, but right now I can see no reason to spend any more on the brakes; as far as I'm concerned, this is problem solved.                                                                                                                                <br>As observed a few days back, I'd deal with Performance Braking again any time - I don't know how they compare on price, but I doubt there's much in it, if anything, and I like dealing with experts who share their know-how and want your business.<br>Hope this helps.<br>David

[Sy V]

A word of warning here.<br>I am researching exactly what pads are available for the HiSpec brake calipers...I suspect we'revery limited in choice because the pads that fit are old Volvo patterns...I'll update when I have  facts.

[davidjt]

Dico<br><br>The fluid is Dot 5.1 Synthetic 'Pro-fluid' with a boiling point of 260C. - Less impressively, you get it from Unipart at around £6 for 1/2 litre. We rejected the serious racing fluids as way over-spec for my purposes.<br><br>David

[philip_sloper]

[quote author=Dico link=board=suspension;num=1094668951;start=30#38 date=02/21/05 at 09:59:39].<br><br>i think i just like to confuse myself in a strange kind of way  [smiley=crazy.gif][/quote]<br><br>I think you will be OK if you go for DOT 5.1.<br>There isn't a specific thread about brake fluid on this site but whenever the subject has come up that is what everyone upgrades to IIRC.<br>I have used it without problems for over 2 years.