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lidistick

Spongy brakes

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Meh.

10 laps around the new A1 GP circuit and my brakes are kinda mushy.

Rotors are in good nick and pads are still good, so what gives?

BTW, the track is in primo condition. Managed to hit 175km/h on the back straight and braking 75m before the chicanes. The auto sucks balls for track days tho so I suppose a manual conversion is going to be needed before the next one :)

Cheers.

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When did you last change your brake fluid?

Agreed, basically after every good run at the track you should change your brake fluid. After taupo I had to also change my auto trans fluid.

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Better change and upgrade the brake fluid.

10 laps of most circuits flat out will cause serious brake fade in normal cars.

Hence, the reason you should do this upgrade, before looking for more power. Ask 'The Rat' how much fun it is slamming into a wall.

Look at http://www.racebrakes.co.nz/ for tips

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what car is it in? sounds good...who you go to the track with?

sounds like it could be brake hoses...old rubber hoses may split or weaken and be bulging now under braking...new rubber or stainless hoses usually fix it

fluid itself (as long as it bled, and they dont really unbleed) wont make it that much more mushy after the track, unless you seriously hammered the brakes

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Car is an E36 328i.

Last brake fluid change was in July with standard BMW fluid.

I went flat out from Lap 5 after learning the lines.

As much as I'd like to upgrade the brakes, I'm currently half-hearted about continuing to track this car vs purchasing a type R and caging it and doing the whole works. there were 2 type R's on the track and they lapped an M3 CSL and a supercharged Holden with 380wkw. They would've passed the GT3 too but it was too quick on the straights.

Transmission is still sweet. Sports mode is pretty useless in the E36. Refused to downshift coming out of the corners so I was pretty slow being stuck in 3rd.

Tires are fine amazingly. I expected chunks of rubber left on the track but I guess 41psi held up. :D

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Not uncommon for road cars to suffer from some loss of brake performance on the track.Is one reason why the intermarque at Manfeild is only four laps

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If you're going onto the track for fun you need to put in decent race fluid with a higher boiling point than the BMW standard stuff.

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If you're going onto the track for fun you need to put in decent race fluid with a higher boiling point than the BMW standard stuff.

Agreed.

I'll probably get some Motul RBF or Castrol SRF for the next track day. I thought brake fluid would be the last of my issues on the track and that pads would be my no1 enemy. Not bad for standard pads to withstand the abuse.

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SPONGY BRAKES! Good Fun HaHa! [it always happens at the worst moments]

Everyone on this thread has pretty well answered your Question. Brake fluid is hydroscopic [it attracts moisture] it is the water content that is boiling under high temperatures. So get a DOT 5.1 fluid

Sometimes the brake pedal is soft for part of its travel ,then hard before it bottoms out [this can be un-nerving in race traffic] This usually is pad knock-off caused by sideways movement in the discs under hard cornering loads[wheel bearing clearances etc] that's why calipers [or discs] are floated on race cars as well as using long-travel master cylinders.Most drivers give the brakes a light pump while driving to take up any clearances

personally I'd use dot 5.1 fluid in my car and have a spare set of pads for track days [i've had great results fron 'Carbon Metallic 90' pads on stock brakes] don't use them for 'cold' day-to-day driving as they're bit aggressive on the discs when cold

Auto's suck on the track [get a syncrosmash]

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Meh.

BTW, the track is in primo condition. Managed to hit 175km/h on the back straight and braking 75m before the chicanes. The auto sucks balls for track days tho so I suppose a manual conversion is going to be needed before the next one :)

Did you use the full length or the new 'club-half' of the track?

I was playing the 'Idiot factor' in my mates Sentra Cup car a couple of months ago, I was turning in off the straight[into the chicane] at 160kays under full throttle with my mate sitting beside me [the latest braking he had ever seen] The track is great.Apart from the pit-wall there is no major obstacles to come into contact with your car [except for moving chicanes]

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The track was track 4. Full length 3.5kms.

The chicane is pretty cool. I like it. Tricky as hell to get right but once you nail it.. feels pretty awesome. Not worried about the pitwall.

Motul RBF is acutally rated Dot4. Has a very high dry boiling point. I didn't get that this time and Greg @ Carsport told me he filled the car with Dot 5 fluid. I believe Dot5.1 is silicone based and slightly different.

If I do make this car a track car, it will get a manual box and a proper brake set-up so I can keep at it and not limp home with soggy brakes. :o

Cheers.

:)

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Dot 5 is different to dot 5.1

You can use Dot 5.1 as an upgrade to dot 4 but don't use dot 5.

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there were 2 type R's on the track and they lapped an M3 CSL

The CSL driver would have been taking it easy ... aint no way a type R would cain one of these ...If my 330i can teach Type-R's a lesson .. then a CSL at full noise would make mince meat outta them...

The not tracking your daily thing is a good option ... track days are awesome, but do make you think twice sometimes :)

Buy a 325i .. join the BMW series :D open class for the win :D

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Dot 5 is different to dot 5.1

You can use Dot 5.1 as an upgrade to dot 4 but don't use dot 5.

My bad. it was 5.1 :)

currently undecided about getting a dedicated track car vs daily/pt track car.

If I can get a good price for the 328i then yes I'll try and get a cheap and reliable track car.. which will most probably mean a Type R. I think there is resistance tho from the significant other with regards to selling the BMW and buying a Honda. Oh well.

:wacko:

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I suppose it was inevitable but my rotors have cracked. The left front has a nice linear crack about 4cm long and I've failed my WOF. I'm taking this opportunity to get upgraded rotors and stumbled upon...........

Posted Image

Posted Image

$195+GST.

Getting some Hawk HP+ pads ... should hold back the fade for the next outing. :)

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Changing your rotors will not reduce brake fade.

Hawk HP Pads? What the f*ck are they? Buy a decent brand.

Brake fade caused by the water content in your brake fluid heating to a point that it becomes a gas (and hence compressible).

They are very nice looking rotors though. They don't look vented though. Are they?

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Agreed changing rotors will not affect fade but as a whole, ie pads, rotors and fluid upgrade, I should get a few more laps before fading. Rotors are vented. I priced up some mintex 1166 and they were $250 a pad + GST! I've heard good things from people doing the targas and they have had no issues with Hawk pads. I believe that Alex from Carspot also uses Hawk pads in his E30 race car.

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Hey Mate if you are serious about track work, get steel rotors [not cast]

otherwise use 'performance friction'-carbon metallic 90 compound pads [they are probably the best compound available when using stock brakes]

If you use you car as a daily driver as well get a spare set of stock pads [and a spare set of race wheels] and change them at the track

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Hey Mate if you are serious about track work, get steel rotors [not cast]

otherwise use 'performance friction'-carbon metallic 90 compound pads [they are probably the best compound available when using stock brakes]

If you use you car as a daily driver as well get a spare set of stock pads [and a spare set of race wheels] and change them at the track

Nah.. not serious enough to be competitive.. but at least have a few more laps before my brakes fail. I have been looking for cheap 16's or 17's so I can fit some semi-slicks. Problem is most of the 16's or 17's are HEAVIER than the BBS RC's that I have.

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Nah.. not serious enough to be competitive.. but at least have a few more laps before my brakes fail. I have been looking for cheap 16's or 17's so I can fit some semi-slicks. Problem is most of the 16's or 17's are HEAVIER than the BBS RC's that I have.

For casual racing don't worry about the weight of the wheels, get a cheap set of 17x8's [or 17x9's] that way you can use all the Slicks that the NZV8 boys throw out of their toybox [usually $80-$100 each] the tyres should get you about 3 seconds on taupo.[swap them to drive home]

Get some adjustable platforms for the struts and mark 2 camber settings.[street & track]

You really should have stiffer springs for the track, but stiffer anti-roll bars will compensate

Trust me on those Carbon Metallic '90' pads. I managed 30 minutes non-stop around Taupo [old-track] in a Cortina with a passenger using standard brakes [there was no brake fade, but I did boil the fluid over coming into the pits] The "90's " will be agressive on the discs when cold, so heat them up [& don't use them on the street]

After writing this, I'm thinking about doing the same to my E36

Join Taupo Car Club they have a neat winter series

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Hawk HP Pads? What the f*ck are they? Buy a decent brand.

Hawk HP Plus are very very good. Compareble to Ferodo ds2500. A great pad for street/track.

Ash

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OEM pads are what I reccomend for Nana driving [street], Change to carbon-metallics for the track [it's a simple job] I don't like compromise street/track pads ,they chew discs when cold & fade at the track when hot! [unless you drive like a Nana at the track as well]

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Its taken me a while but I've finally done the lot.

Hawk HP+ pads front

Bendex back

Motul RBF 600 fluid

Goodridge braided brake lines.

The fronts squeal like a virgin around town once warmed up. Don't really notice it with the radio and windows up.

Braking performance.

My original pads were 75% gone so it was sorta a good time to get them changed.

Going up and down the Kaimai's is a different experience. I can definitely brake a lot later and there is much better feel; I can brake hard right until the point before ABS kicks in. I think my stopping distance has shortened.. probably because I'm more confident of standing on the brakes. But the biggest improvement has to be the pedal feel. The original rubber hoses were 11years old but were still in reasonable condition. It was a good excuse anyway ;)

The new pads dust like mad. Meh.. I have a water blaster so its all good :D

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Get some adjustable platforms for the struts and mark 2 camber settings.[street & track]

You really should have stiffer springs for the track, but stiffer anti-roll bars will compensate

After writing this, I'm thinking about doing the same to my E36

Join Taupo Car Club they have a neat winter series

I can't be bothered with adjusties. I'm not that competitive and track the car for fun. Its already had a suspension makeover (bilsteins and H&R springs) and I may get stiffer anti-roll bars (I believe Whiteline do an E36 set) and an X-brace from the US. ;)

Winter series? Sounds tempting. :D

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