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fendervg

288s and master cylinder size

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Wondering if anyone who has a 288 front brake conversion on their VR6 has fitted a larger master cylinder to improve pedal feel - I know you need to do this on a MkII Golf when fitting G60 callipers.

 

Is there a larger one available ? Maybe a MkIII VR6 item ? My pedal still feels soft and has a lot of travel, although it really bites when you brake hard.

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Yep, same complaint everyone has of the 288s. A long pedal and poor initial bite.

 

Cheapest and easiest option is to use pads with a very high coefficient of friction, but it's hard finding any for the ATE caliper.

 

It's not worth using a Golf VR6 MC as it's the same size as the Corrado's (23mm). It might be worth investigating if very late / run out OBD2 Golfs got a bigger one though as they have a different ABS system with no proportioning valve and the pedal on that car is night / day better than the Corrado's.

 

My gf has an 06 Polo GTI which has the 288 brakes on it and they are massively more powerful. Ditto MK4 Golfs with the same brakes. It's a combination of bigger MC (24mm) and better brake pedal (fulcrum point in a different place for more leverage).

 

It's not going to be cheap or easy to retro fit these parts to a Corrado, especially as the Corrado's MC has a weird fitment, so you'd have to replace the servo as well.

 

I looked into all this years ago and it was far easier to just fit some bigger brakes, but it's expensive due to needing bigger wheels and tyres as well, but the performance is staggering compared to 288s/312s.

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Cheers Kev - sounds like there is no easy solution - although I am going to try and bleed the m/c anf ABS as some people seem to have found that this makes an improvement.

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Yep, same complaint everyone has of the 288s. A long pedal and poor initial bite.

 

Sheesh - I'm just about to fit some 288s that I've been refurbishing, in order to improve on the standard 280s :( :(

 

And I thought 'everyone' said that the 288 upgrade was a worthwhile path to better brakes without having to also go for bigger wheels :(

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You shouldn't need to as the piston size of the ATE calipers (288 / 312mm) is 54mm - ie the same as the standard Girling 54's

 

When fitting G60 calipers to a MK2 with 239's you need to do this as the standard master is only 20mm.

 

I'm running 312mm brakes on mine with a standard but brand new 22mm non ABS MC and they feel fine.

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Don't forget it's the VR6 in particular that suffers this long pedal problem mate.

 

Don't panic John, the 288s are better than the 280s, significantly better. It's just that the pedal isn't as nice and needs a firmer shove, but they do stop you effectively. You just need a good pad.

 

And speaking of which, I've done my 288 pad research and discovered they are expensive and have limited choice of materials. I think I'm going to try the Ferodo DS Performance at £100. DS2500s are £150 and the good pagids are £200!!! Standard fit pad on the Polo GTI Turbos (Lucas 288s, but same pad as the ATE 288) and I really like the feel and power of those.

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Still going to do a complete flush when the weather improves with ATE Blue fluid. Managed to get some air out of the m/c today, and the brakes come in earlier and it has made a slight improvement.

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Good stuff. Might be worth bleeding the 2 nipples on the ABS pump too, although you should just need gravity to drive the air out of those.

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hmmmmm,interesting thread to me as i have got a '97 vr6 golf in my garage that i am stripping to get all the ob2 stuff out of. Today i was taking the exhaust off and I did notice that there was no bias valve on the rear axle and thought thats odd because the mountings were there for it.

So the different abs system explains it. When i take the servo out and master cylinder i will investigate to see if it does differ from the corrado one.

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/\ Yeah that would be good. Could you also see if there are any pedal box differences? I suspect the later cars got a better pedal arrangement for more leverage on the MC.

 

Would you also be able to get the part numbers off the ABS pump and ECU for me?

Thanks!

 

I'm going to replace all the brake lines on mine and I would rather dump the rear bias valve whilst I'm there. Should be able to get 97 VR6 ABS parts fairly cheaply from a breaker.

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Surely greater leverage would result in a more mushy pedal? More power, sure, but worse feel.

 

You could be right. I haven't actually looked at the pedal in any detail yet, or a newer car for comparison, but the below sketch hopefully gets across what I'm thinking!

 

In the pic I've drawn 2 MCs. The red one is where I suspect the VR6 one is positioned in relation to the pedal fulcrum, and the black one is what my mind is suggesting is more ideal for stronger braking power. I'm just thinking that where the red one is positioned, the pedal runs out of movement too early? The black one gets a bigger and longer shove?

 

What say you guys? It's not my area of expertise, I'm just guessing :D

 

I know if you increase MC bore, you increase pedal travel, but increase power, so how to the OEs get very strong bite at the top of the pedal travel?

 

Oh and assume both MCs are actually attached to the pedal and not floating :lol:

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/\ Yeah that would be good. Could you also see if there are any pedal box differences? I suspect the later cars got a better pedal arrangement for more leverage on the MC.

 

Would you also be able to get the part numbers off the ABS pump and ECU for me?

Thanks!

 

I'm going to replace all the brake lines on mine and I would rather dump the rear bias valve whilst I'm there. Should be able to get 97 VR6 ABS parts fairly cheaply from a breaker.

 

Yes no problem, if you are wanting the abs parts then i will have them going cheap as im breaking the entire car, all i want is the obd2 stuff,all the rest is being sold

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Yes no problem, if you are wanting the abs parts then i will have them going cheap as im breaking the entire car, all i want is the obd2 stuff,all the rest is being sold

 

OK, thanks! In that case, if you wouldn't mind extracting the ABS pump and it's associated fittings / brackets, ABS ECU and the ABS ECU loom (without snipping it) for me and putting to one side, I'll take them off you. No rush though. Just PM me when you're done.

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Well - my 288s are on at last, and I have to say that the dreaded 'long pedal' doesn't seem much if any worse than when the old 280s were on.

 

So, I'm quite a happy bunny.

 

I'm using the part worn discs and pads that came with the 288s untill after the worst of the winter is over, so I'll report here my thoughts on Ferodo's DS2500 pads and Brembo plain discs when I fit them in the New Year.

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If a larger MC is needed a 25mm version can be fitted. The master cylinder is made by ATE, VW# "441 611 021 a" brake master cylinder for 200 turbo/200 turbo quattro.

 

audimc.jpg

 

Couldn't say if this is useful for the upgrade being discussed but useful part no. if anyone wants to increase the MC.

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Do VW 288 front discs and the rears come with an anti-corrosion coating nowadays ? I know some other brands do, but wondering if VAG have them, as they tend to last longer.

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Get Brembo max from GSF. They seem resist warping better than the VAG discs. Vag discs have a grey coating but it's certainly not rust resistant.

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the grey paint is more to do with storage of the parts and removing the need to carefully degrease new discs (unpainted ones are lightly oiled to prevent corrosion before fitting),

it does seem to protect the unswept parts of the discs on the car for a fair while, both the front discs on one of my cars (been on for nearly a year) and the rears on my other have little corrosion, but I'm sure a full winter of salty roads will put pay to that.

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Kev, Heres some pics of what i have removed for you. I have took a pic of the sensors,the fronts look the same as the corrado ones and im unsure on the rears?? Dont know if they are the same or not,maybe you can tell from the pic? I will be taking the rear beam off the golf this weekend hopefully so i will try remove the sensors without breaking them for you.

So i think thats the entire abs system?

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Just did a quick bleed of the m/c and abs pump today - no one had touched the pump - the nipples were nearly seized, and there was some air in the m/c as well. Forgot to kill the brake vaccuum by pumping the pedal first though!

The brakes are now better - still a fair bit of pedal travel but much more powerful.

 

I'm going to take it to VAG to get a proper pressure bleed done - and if that doesn't work give it a full run through with ATE Blue racing fluid and eazy bleed.

 

Next up is the aux water pump, and then sunroof repair.

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