Brake cooling / pads

Brake cooling / pads

Author
Discussion

futie

Original Poster:

653 posts

277 months

Tuesday 1st April 2003
quotequote all
I'm doing my first track day in the Cerb in May at Brands and am a little worried about warping the brake discs.

It's been suggested that a cheap solution might be to add some cooling ducts to feed cool air onto the front discs. I haven't had a chance to have a good look, but I imagine that I could open up the vents under the front indicators - anyone done this? Is it possible?

Also i'm told that Mintex 1155 pads might be a good idea, but people have also talked about 1144's, and Ferodo DS3000's. Which would be a better match for my standard discs? How much do these cost - and where would I get 'em?

TIA

BCA

8,626 posts

258 months

Tuesday 1st April 2003
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Not sure about the warping, but a quick search on here/ egroups will reveal several topics on the matter. I think William Ball is the man to talk to, he does alot of trackdays and has his own cooling deflectors under the car.

>> Edited by BCA on Tuesday 1st April 23:03

monkeyjunky

418 posts

285 months

Wednesday 2nd April 2003
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I run 1144's are they are great on track. You do need to keep them warm, I very nearly took a trip to see Mr Gravel Trap at copse having followed a Tamora slowly round for two laps. Personally, unless you are a very experienced track driver, I wouldn't be overly concerned about warping the disks. Get good pads and change the fluid, AP Dot 600 is very good stuff (track use only of course ), make sure you have a cooling lap and all should be fine.

futie

Original Poster:

653 posts

277 months

Wednesday 2nd April 2003
quotequote all
I'm only concerned about warping as I seem to have warped two sets of discs already - and that was just road use!

I don't think i'm a particularly experienced/good driver; it's probably just excessive use of the brakes and perhaps no warming-up or cooling-down period. But one thing's for sure- I want my brakes to be 100% for the track!

Interesting you mention about brake fluid - that's something else I thought I might change. How come the AP stuff is track only?

kevinday

11,641 posts

281 months

Wednesday 2nd April 2003
quotequote all
Guys read this link, it is all about pads and bedding them in, not warping discs.

www.stoptech.com/whitepapers/warped_rotors_myth.htm

futie

Original Poster:

653 posts

277 months

Wednesday 2nd April 2003
quotequote all
Oo-er, so the deal is that I should buy the right pads for the right job, and bed 'em in properly by driving like a loony for 10 minutes as soon as they are fitted! No - only kidding!

davidy

4,459 posts

285 months

Wednesday 2nd April 2003
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Although not in a Cerbera I have a number of trackdays under my belt (>70) in various cars and have the following comments:-

1) Mintex Pads 1144s are a very good compromise and work quite well from cold (I'm surprised that minkeyjunky had an issue, maybe the pads got glazed see below). 1155s are a different issue, had these fitted to a Prodrive Impreza, absoultely useless until warmed up and very dangerous initially on the road.

2) Brake Fluid, buy the best you can afford and change it regularly (I boiled a silicone DoT5 fuild at Cadwell one year and after that I switched to AP550 (one down from the 600) which I used in my road and track cars. The high performance fluids are more hydroscopic and therefore should be changed more frequently (every six months at the latest)

3) No brakes on the circuit, two things tend to happen on circuits which you don't necessarily get on the road, the first is that all braking applications tend to be fairly hard and you can glaze the pads (this can be solved by using grooved or drilled discs, which will chew up the pads, or by removing the pads and roughing them up), the other is that if you have any play in the wheel bearings (or slightly warped discs), the higher speed vibration, will knock the pads back further into the caliper requiring a firmer pedal push next time (or a pump on the pedal)

4) Cooling, ALWAYS have a cooling down lap ideally using the brakes very little if at all, to give them a chance to cool down (it can also help to go for a longer trip back to the paddock, service roads (even public roads) to really get them to cool down (remeber to remove tape and numbers if you go public.

5) Take it easy, there is far more to be gained from being smooth (with all the controls) and getting the lines right than being the last of the late brakers

6) Have Fun

davidy

williamball

4,279 posts

283 months

Wednesday 2nd April 2003
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Agree with pretty much all said before.

Change fluid before you go unless it was changed VERY recently. You will give it a hard time. Use best fluid pennies can buy.

Mintex 1144 are fine [I used them for a while], IMHO Ferodo DS3000 are miles better, but the are very noisy and not as effective when cold.

Remember if you are fitting different pads to put the same type on back and front. Don't just put uprated pads on the front as that's where most of the braking is otherwise the front/rear brake bias will change as the brakes heat up. So, if it's different pads, it's different pads all round.

In terms of cooling, if the car is running at standard height with decent pads and fluid, then you shouldn't need to do anything else. However, I have little flat 'plates' attached to the front lower wishbones, so the front edges sit below the level of the car. The wishbone is angled back to in theory they direct more air into the wheelarches. Dunno if they really work, but I think they do. You'll have to experiment with sizes to stop the wheels fouling on full lock, but mine are just thick plastic sheet attached to the arms with 2 jubilee clips. I don't think you'll need to go to this trouble though.

WB

futie

Original Poster:

653 posts

277 months

Wednesday 2nd April 2003
quotequote all
Where does everyone recommend getting their pads/fluid from? I'm near Guildford, Surrey so hopefully someone around here will sell this stuff?

gazzab

21,109 posts

283 months

Wednesday 2nd April 2003
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I am near Guildford as well! I would just ask Andy at APM if he could source and fit. He doesnt add enormous mark ups like others do.

davidy

4,459 posts

285 months

Wednesday 2nd April 2003
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I used to live in Chobham and used AutoCross just north of Bracknell at Binfield, nice helpful guys and good pricing too

davidy

dannylt

1,906 posts

285 months

Wednesday 2nd April 2003
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Could I interest sir in some nice 8-pot Brembo's with maximum size discs for the 18" wheels? Must put the advert up! Fitting included in the price!

futie

Original Poster:

653 posts

277 months

Wednesday 2nd April 2003
quotequote all
You could definately interest me, Danny! But I need to get 18" wheels first!

PS. Had some bloke up north called Julian try to palm off some dodgy tuscan discs and calipers onto me the other day . They didn't fit though . Don't suppose you took your 18's off before you sold it did you ?

dannylt

1,906 posts

285 months

Wednesday 2nd April 2003
quotequote all
Nope, no wheels unfortunately. Worth getting just for the brakes, obviously!

I'll put up the advert later today/tomorrow - just need to find some piccies.

danny

yellow peril

5,131 posts

273 months

Wednesday 2nd April 2003
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Used my Cerb 4.5 at Bruntingthorpe on Saturday and despite giving it some around the track and braking from 170mph,(speedo reading)stock factory brakes remained good.

Last year at Castle Coombe discs went blue and distorted requiring re skimming.

What's changed? car now fitted with 18" Spyders.

Could these improve airflow to the
brakes?????

Used cooling down lap at both venues.

Anyone have any comments please!

dannylt

1,906 posts

285 months

Wednesday 2nd April 2003
quotequote all
Braking once from high speed occasionally is fine. Doing it multiple times, i.e. on track is what hurts - the temps get higher. Braking style is also a big faster, apparently shorter and harder is better because the discs have less time to accumulate heat.

daver

1,209 posts

285 months

Thursday 3rd April 2003
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dannylt said: ...apparently shorter and harder is better.

I bet you say that to all the girls.

RichardP

74 posts

284 months

Friday 4th April 2003
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I have a 4.2 on 16” wheels in which I’ve done approx. 15 track days. I have never warped the discs but eventually they do get heat cracks. After trying Mintex and EBC pads (red & yellow) I’ve eventually settled on Mintex 1155s which are excellent on the track and also work from cold on the road (unlike the EBCs). I was finding that the rear brakes locked under hard braking on the track (a characteristic of 4.2 brakes) so set about rectifying this over the winter without going to the expense of bigger wheels in order to accommodate bigger brakes.

The solution was to get a pair of old 4.5 discs which are 322mm (thanks to Joolz for those) and have them turned down to 315mm. If you fit the hub/calliper spacer that is used on the 4.5, the calliper still just fits inside the 16” wheel. The only downside is that the outer edge of the pads overhang the disc by approx 2mm. I tried them on the track for the first time last Saturday at Cadwell and they are excellent. The brakes now feel perfectly balanced and neither end locked up. That was probably the first track day where I’ve had complete confidence in what the brakes were going to do each time. The added bonus of going to 315mm is that it is now a standard AP size so replacement rotors can be bought from any AP stockist. I have also drilled 3 x 40mm holes in the access panel in the wheel arch, directly behind the front indicators, to aid cooling. I haven’t fitted any ducts but assume that any extra air entering the wheel arch area is going to be a benefit.

I’m using AP600 brake fluid.

Hope the above helps.

Richard