Master Cylinder Fixed - I HAVE BRAKES !!

[benm]

Well I finally got my car back today after having the master brake cylinder bored and sleeved. They had my car for 4 days (about a day longer than it was sposed to take) and it cost me $395 all up (remove master cylinder, courier to workshop in the city, sleeve and seal, re-fit to my car, new brake fluid and bleed the brakes). I swear my car has gone through more bottles of brake fluid this year then engine oil, I can think of 4 bottles off the top of my head.

The brakes are deffinetly better now but im -still- not 100% happy after the amount of money i've spent. The brake pedal still goes down quite abit before any actual friction is noticed. The only thing I can think of right now is that im using RB74 front pads which are probably alittle too high quality for just normal daily driving to work and back (ie; 50-60km/h streets with no -heavy- braking), so they don't get a chance to get up to operating temperature with no heavy braking being done.

I'll leave it until after Xmas and then get a set of Bendix Advance/Ultimates and try that out.

Does anyone know if you can adjust the brake pedal like you can the clutch so that you dont have to push/release as much before friction is applied? I want friction to be applied about 1.5-2cm earlier then what my pedal is actually moving.

I guess the only way I will really beable to see how things hold up is the next track day I attend so that I can get some decent heat and km's into them and see how everything holds up.

The full setup is now as follows:

* Front/Rear - DBA4000 Slotted Rotors

* Front/Rear - Calipers overhauled

* Front - Goodrich braided lines

* Front - RB74 Pads

* Rear - Comp2 Pads

* Master Cylinder bored and sleeved

* Master Cylinder brace

Hopefully this setup will last the lifetime that I have the car (at present the next 25 years haha).

[jlnewton]

Wow, you would have too much left in the brakes department to replace would you??? Not sure on the adjustment, as far as I am aware it is all self-adjusting. Think twice before going the bendix ultimates, as I have basically the same setup as you but with the ultimates and the are seriously dusty. I have no problem with their performace, even at the track, but the dust is amazing. Hope its all fixed!

[B-Man]

Ben - that is a bit better than what you thought it would cost for the final re-sleeving , isn't it ???

Nice work !

[benm]

Yeah my original quote was $600 but I took it to a local brake place and they quoted me $450 but ended up getting it for $395, not sure why but I aint complaining.

I'll get 1 of my mates to give the brakes a go and see what he thinks. Mine might be normal just that im expecting something better, who knows

[Duncan]

brakes...they can be handy but I find they only slow me down....but no excuses not to come along to trackdays now

Good to hear its all fixed, turn 1 at EC is no place to find you have a brake problem!

I use the ultimates myself and have no complaints about noise, cold stopping or hot hot hot stopping. As jlnewton said tho, they are outrageously dusty.

[benm]

but no excuses not to come along to trackdays now

I need some tyres Not sure if i'll just buy some 2nd hand stock rims with normal rubber and just wear em to the belts or some 2nd hand stock rims with some semi-slicks (or even cheap slicks).

Good to hear its all fixed, turn 1 at EC is no place to find you have a brake problem!

You mean like I did at the last trackday I was at ? Lucky it was the beginning of the cool down lap though

I use the ultimates myself and have no complaints about noise, cold stopping or hot hot hot stopping.  As jlnewton said tho, they are outrageously dusty.

I don't have any dust problems, probably to do with the slots in my rotors cleaning/shaving the pads and removing the dust.

I took my car for abit of a drive tonight up and back on the Hwy. I'm getting used to the feel of the pedal now, its consistent and strong no matter how much or how hard I brake (only did about 20x <80km/h stops).

[Neil]

Please excuse my stupitty but what brand are RB24's?. Not that I'm about to change cause I know what works,,,just interested all the same.

Neil.

[benm]

www.racebrakes.com.au <- they are the brand of these guys. Higher temperature range then the Bendix series but slightly harder on your rotors.

[Peter Behrens]

benm;

Just a note on the master cylinder brace. In the recent past I had a close look at the ones available on the market. Including the ones that are incorporated on the strut tower brace and wasnt really impressed. Most looked like an after thought. So in the end i designed and built one myself out of a adjustable hiem-joint. The after market ones seem to rely on the two small mounting bolts on the strut tower to take the entire load of the flexing or the firewall and master cylinder. These was, as far as i could see, still flex because the master cylinder pushes foward and slightly inward towards the center of the motor. to eliminate this I built a bracket that uses the strut tower only as a mounting point and the load is taken by a bracket that raps partially around the strut tower. It was a bit of a bitch getting the geomtry right but worth the effort in the end.If you need a squizz at it let us know.

Hope this helps

Peter

[Duncan]

"RB"74 is Race Brakes, the top bunch of blokes who give SAU NSW club members a discount

as for "2nd hand stock rims with some semi-slicks" I've got a set of those for sale with D01Js on them...you may have to fight dan for them tho!

[JimX]

The brakes are deffinetly better now but im -still- not 100% happy after the amount of money i've spent. The brake pedal still goes down quite abit before any actual friction is noticed. The only thing I can think of right now is that im using RB74 front pads which are probably alittle too high quality for just normal daily driving to work and back (ie; 50-60km/h streets with no -heavy- braking), so they don't get a chance to get up to operating temperature with no heavy braking being done.

You're the only person I know of with RB74's who has this problem, so you can almost certainly rule out the pad compound. It's possible that they weren't broken in properly and the pads are glazed though. You might want to pull them out and sand them back and re-break them in again to see if that helps. But I'm almost 100% sure it's not the pad compound itself to blame here.

The RB's get up to proper temperature after 1 or 2 stops and stay warm enough thereafter unless you do a lot of highway driving in between braking. But even when stone cold in the middle of winter, I never found them to be squishy at all once I'd left my driveway. And they only got better from there.

[benm]

It's possible that they weren't broken in properly and the pads are glazed though.

I had RaceBrakes do this for me (I went out as a passenger with him). Its amazing how many faults he found with my braking setup just by doing 2 laps around the block (I guess being a rally driver you pickup those things pretty quickly).

my brakes aren't fading just the pedal is low to begin with. I need someone in the know to take my car for a drive and see what they think as I may be just over-reacting.

[red900ss]

Ben you may just be thinking about it too much. I can't tell you how many times I bled brakes and thought "oh the pedal feels crap" only to get out and use it and realise they were fine.

Give it a little while to get used to, my pedal feels pretty light, but they do kind of bite straight away....

[benm]

Yup I think its all in my head (or foot) too. Just got back from having my free 5,000km tyre balance and rotation... On the drive home my brakes felt 110%. I was tempted to go back and ask them what they touched (knowing that rotating tyres wouldn't solve my pedal problem) but then I thought it could have been coz they adjusted my seat.

Anyhow it all feels 110% now, couldn't be better.

[YEE-HAA]

Benm,

Your not imaging it! I had Bendix Ultimates in my car (front only), and the pedal was noticably firmer right from go- to-whoa! (Sorry! Couldnt help myself!).

I then replaced them with Bendix Advance, and the pedal became a little softer!.

But as with what other peolpe have said, the Ultimates stop on a dime, I have to admit that! You cannot fault it for that! But yes, they dust! Boy do they dust! That was the main reason why I went back to Advance, especially seeing as I mainly travel to & from work and dont hammer the brakes that much.

So Im content to trade off a softer pedal for cleaner wheels longer!.

Hope this helps.

[benm]

hrmm my pedal still feels.... "weird".

I got Merli to drive it last Sunday night and he couldn't fault it (did about 5 70->20 km/h stops) and he said it felt alright.

I just had a full car load (4 people including me) and the pedal was nice and firm with no heavy braking just regular daily driving. But then an hour later it was just me and a passenger and my pedal was constantly much lower. I need to get some Bendix pads for the rear coz my Comp2's are squeeling (black paint got on the pad surface) so hopefully the pedal fixes itself then or I might just get someone to re-bleed it (apparently having ABS makes it trickier to bleed it "properly").

[Nightman]

Hi Ben,

I could be way off beam, but maybe you have a booster prob? A leak perhaps? Faulty Valve??? Worth a look perhaps? Thats my 5c 2c is long gone!

[benm]

My car will be back at the mechanics workshop all day Thursday to see if they can find the problem.

[benm]

Got the mechanic to re-bleed my brakes today in an effort to try and fix the inconsistent pedal. Before I dropped it off to him it was:

pump+pump=brake, pump+pump=brake.

Now after the bleed the pedal is just consistently low (grrrr x10000) but it still stops very nicely. To test it I wanted to murder them abit to see what they really felt like (I also wanted to test the K&N Panel Filter I put in so I wasn't exactly accellerating slowly between stop) so I did:

60->20km/h

60->20km/h

60->20km/h

stop and turn around

60->20km/h

60->20km/h

60->20km/h

stop and turn around

100->20km/h

100->20km/h

100->20km/h

stop and turn around

130->20km/h

130->0km/h

stop and turn around

60->20km/h

60->20km/h

60->20km/h

(90sec of 50km/h driving not using the brakes at all)

80->20km/h

80->20km/h

stop at lights.

...then I just drove home normally the rest of the way (about 3km). The brakes smelt quite nice when I got home

Now whilst I couldn't notice my pedal getting any lower I was hitting the ABS on the 3rd set of 60->20km/h braking as it was a different road (the smooth type of tarmac) where as first 4 sessions were all done on the rocky type of tarmac so I guess the brakes were still biting pretty hard at that stage. Infact... I think they just wanted to keep on going n going but I was starting to annoy afew people on that stretch of road so I decided to go home.

Now If I can get the mechanic to workout why the pedal is consistently low and fix it back to being consistently firm i'll be quite a happy camper.

[JimX]

Something doesn't add up. If the pedal was high<->low before the bleeding, then surely if that was the problem it would be consistently high after bleeding? I can't see how air in the lines would let the pedal go any higher at all. That would imply that the fluid is more compressable than the air.

This is a weirdarsed problem and it's probably got the simplest solution! You just need to figure out what it is.