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Brake IssueHi Guys,
I went out for a blast last weekend on the quiet country roads and noticed something strange with the brakes. With my current setup I have what I would class as two stages of braking. The first is when I gradually brake, the car stops gradually as normal. The second is when I slam all on, the discs start scraping layers off the pads, you hear a slight grinding which is normal and you stop much quicker. The problem I had was that after a lot of accelerating, braking, accelerating braking between twisty corners and short straights, the brake pedal started to get harder to press. After a while i was having to use the force of a stage 2 brake as i call it to do a stage 1 brake as the pedal got really hard to push down. After slowing down and tootling along at normal pace for a couple of minutes brakes returned to normal again. Any ideas what is happening here? Could the brake fluid be getting too hot and overheating? Could the discs or pads be getting too hot? Just curious as if i take it on a track i want to ensure the thing will stop after a couple of laps.. As I wasnt doing stage 2 stops around the twisty roads, just a lot of stage 1 stops, its put me off tracking it for now unless I can identify what caused the issue. My current brake setup is as follows: EBC turbo grooved discs front and back EBC yellow stuff pads front and back Goodridge braided hoses 5.1 brake fluid Cheers Martin
When you say 'pedal got really hard to push down' I take it you had to press harder to get same braking effect. Just thought maybe brake pads jamming in calipers when hot or perhaps brake fade? You could try rebedding the brakes again as you do when new. My PF's seem to stop better when I have repeated this process.
Mike
The brake pedal got much harder to press down. When I did get the pedal down say half way it was braking as normally it would at half way. I couldnt physically get the pedall 3/4 of the way down to make the car stop very sharply... the pedal was too hard. Does this help?
One of the following 3 things
1) You have a servo problem (unlikely). Related you could have a problem i.e leak in the vacuum pipe that comes from the manifold to the brake servo (unlikely) 2) You have not correctly bedded your brakes in. The pads are glazed (wooden feeling) and are transferring heat into the fluid at an excessive rate. Solution is to take themout and rough them up a bit with some very coarse sandpaper. You may also need to have a close look at the disc. (quite likely) 3) You have bought shite discs and pads. Solution is to stop being a pikey and buy some decent ones. It is not a ford. (also quite likely) Grinding noise IS NOT NORMAL. Unless of course you are using a heavily sintered pad. WTF is 2 stage braking? You think to much. Your brakes are not a switch, if they are being applied the force being applied at the discs is down to the force you are mashing the pedal by, unless you have a problem as above. If JP is Roland Rat, them I am Errol the Hamster... His number 1 fan.
Just seen you have EBC's. EBC's suck on every car and bike i have had them on (mainly bikes to be fair), although i have not tried them on a scoob.
They sponsored me for a while. I used to flog the pads on and buy decent stuff while still having EBC stickers on the bike and patches on my leathers. The discs never lasted more than a couple of meetings before they warped. If JP is Roland Rat, them I am Errol the Hamster... His number 1 fan.
The brakes work fine when cool and can brake very sharply if you stamp on them when cool. Would this still be the case if the above applied?
I was recommended these as an Upgrade disc and pad to the subaru standard discs and pads (which are supposed to be rebadged EBC Red Stuff pads according to Subaru dealership). I understand they arent going to compare to AP brake kits but I was quoted 2,800 for front and just under that for rears. Having just forked out for the car, two new tyres etc I didnt have a spare 5-6k to implement AP brakes... this setup cost me around 600-700 notes which fit the budget at the time.. I take it you recommend AP's?
Not loud metal on metal grinding... all grooved discs when stamped on make a noise when braking heavily from my past experience?!
2 stage braking means you can brake lightly are hard...
Well given the budget they are certainly an improvement on standard brakes / pads. They were recommended by both the subaru dealership, graham goode racing and a local garage as being as described... better braking for the car on a budget...
how much who the feck quoted you that price http://www.rogerclarkmotorsport.co.uk/s ... ductID=691 http://www.rogerclarkmotorsport.co.uk/s ... ductID=694 total price £2,367.79 and probably a day to fit both sets if that ! 2007 BMW M5
2004 Petter Solberg STi
Agreed! What a horrifying quote. Stop wasting money and get AP, and go somewhere suitable. AP's do not have to be that expensive.
4 hours MAX to fit. Less than £200 for Adam in Buxton.
totally agree that AP's are the way foreward, I'm sure having the rears makes an even better setup but just front will keep you out of fade territory and 100% confidence that you are always going to stop, and stop quickly. IIRC around £1400 fitted for the fronts. Still a lot of cash but probably one of the best mods I've done!
Why waste your money on AP's when you are never going to use their full potential.
Performance Friction Discs and pads on mine are incredible. The discs cost about £500 for the pair (you can fit yourself) The Pads (z rated) are about £100 for the pair (you can fit yourself) They have never let me down, never faded, never done anything other than stop the car. Discs have done 30,000 miles so far Average for a set of pads so far is 18,000 They work on track or on the way to Tesco's Job done - now use the money you have saved on 3 track days Duncan : www.racedynamix.com
email: duncan@racedynamix.com tel: 07540 185754 Custom Remaps for: All Impreza/Forester 2001-2010 | Classics 92-96 (ESL) | Syvecs (Solaris) | Simtek
This is also a good solution. Had these on my Evo and they are very good brakes.
Yes, it’s perfectly possible
The Subaru dealership that told you that are speaking crap. As said you can get a font AP set up for around £1600 which are absolutely superb. If you want to pop your eyeballs out your sockets and have unbelievable braking even doing track work then get the rears as well. THE best money you will ever spend on a car is on the brakes, so yes i would recommend AP's. It’s a silly argument about wasting your money on something you don’t need. You don’t need an OTT car like a WR1 but you bought one. You don’t need a big fancy plasma TV but you bought one etc..etc..If you can't stretch to to £1600 (AP are the daddies) then get some Performance friction pads etc that a lot of people including Dynamix who know the crack will recommend. I say again - EBC stuff is shite.
Explain the physics to me then? They don’t have to make a noise at all. In my experience of cars (and bikes that all run heavily grooved or drilled discs and you can hear a lot clearer) the only reason you have significant noise from brakes is they have a heavily sintered content (Dunlopad’s were renowned for this), your brakes are worn out – or you get rattling noises from using floating discs or no anti rattle springs etc.
Is medium force stage 1.5? If JP is Roland Rat, them I am Errol the Hamster... His number 1 fan.
With regards to AP brakes I was quoted £2000 ex vat for front and £1900 ex vat for rear. This also excludes fitting. All in it was 5-6K of a job...
Medium braking doesnt exists its either light or hard thanks for your input guys much appreciated. I will be trying to see if it happens regulalry over this weekend as from tomorrow i am off to the lake district for a few days. cheers Martin
whoever quoted u that is having a giggle!
Can I echo what Marky said in his views on EBC brakes. Complete rubbish on a Subaru.
Duncan : www.racedynamix.com
email: duncan@racedynamix.com tel: 07540 185754 Custom Remaps for: All Impreza/Forester 2001-2010 | Classics 92-96 (ESL) | Syvecs (Solaris) | Simtek
you may
Here's my view.
> Could the brake fluid be getting too hot and overheating? No, hot brake fluid leads to boiling of either the fluid (won't happen) or of very small amounts of water abosorbed into the fluid over time. Brake fluid is incompressible, steam isn't. So when you have steam in the fluid the pedal goes to the floor. That's very different to your symptoms so the answer is no. > Could the discs or pads be getting too hot? With rubbish pads the coefficient of friction drops when they get too hot. With a lower coefficient of friction you need to press harder to get the same braking. Press harder and harder and the pads get hotter and hotter. Eventually you can't press any harder. This is called brake fade. This fits your symptoms perefectly. A classic case of brake fade. > EBC yellow stuff pads front and back "With rubbish pads...." There you go. I rest my case. Talk to John Freeth at Performance Braking in Monmouth, 01600 713117, and he will recommend some Pagids that will solve your problems, probably RS4-2-1. Not cheap but you only pay once as they will solve your problem. Or you can get some huge AP's that will be fantastic but to be honest probably OTT for the road. That didn't stop me having AP 6 pots on the front and AP 4 pots on the back though. And they didn't cost me much more than a tad over half of what you were quoted.
Top explanation! I also used Pagid's in a 330mm alcon set up (Prodrive upgrade on a P1) and they were very good, although i never took it on track with them. Another top place for brake stuff (and oils as well amongst other things) is AS performance. Talk to Alyn. Top guy and mega keen prices. If JP is Roland Rat, them I am Errol the Hamster... His number 1 fan.
The only reason I thought about this is that pre-braded hoses, the pedal would get spongy when used a lot which I was told by the local garage was the fluid getting too hot and possibly boiling. Post braded hoses the same sort of time and braking made the pedal go hard not soft. I know braided hoses are designed not to expand and as such it would make sense the pedal getting harder if the upgraded fluid managed to boil. Your explanation does clear this up though so thanks for that...
Okay, I assumed that having grooved discs helped reduce brake fade over standard discs as per the local garages advice. As they heat up, the harder you press the more the grooves dig into the pad and stop you quicker. Your theory certainly sounds just what is happening though. I am cheesed off now with two garages and one performance company for recommending this solution if its common knowledge that the EBC are a waste of time... grrr
Yer the local garage looked it up on his computer and said EBC Red Stuff pads are rebadged original subaru pads and that EBC Yellow Stuff pads are classed as an upgrade pad for the car for better all round performance.
Does the scoob already have 6 pots at the front? Just trying to understand how the AP system is so much better. Are they bigger discs?? Thanks for all your advice guys, a wealth of information is coming out now.
Brembo's front are 4 pots with 330 disc, rear 2 pots with 315discs i think ap are 6 pots with 355disc, rear 4 pot with 335 disc. come standard with ferodo ds2500 pads Name an shame who quoted you £5/6 for ap's 2007 BMW M5
2004 Petter Solberg STi
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