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Model specific boards => Golf mk5 => Topic started by: Hurdy on 07 September 2009, 21:01

Title: Rear brake upgrade
Post by: Hurdy on 07 September 2009, 21:01
For a while I've been umming and erring on whether or not to upgrade the rear brakes.

Generally they fit the bill, but after hard driving they fade and the rear becomes light under heavy braking.Also, now I have the Toyo R888's on I've found that with the extra grip they give the rear is lighter than ever, so I finally took the plunge and have gone for some uprated rears

Full upgrade to OEM R32 brake set up.

Why the R32 set-up?

Because I am hoping that the ventilated discs will give better cooling and so less fade
Because they are larger than the stock GTI/ED30's and should help a little with the light feeling at the back, which is basically a wierd sensation of the rear feeling like it is pushing the front and wanting to overtake the front of the car.....if that makes sense!! :laugh:

Should be on the car by Monday and I'll report back with pics :cool:

Any advice on other set-ups is still welcome because if these don't do the trick I'll have to bin them and consider something else anyway :smiley:
Title: Re: Rear brake upgrade
Post by: Rhyso on 07 September 2009, 21:02
you don't hang about with these upgrades do you!?  :shocked: :shocked:
Title: Re: Rear brake upgrade
Post by: bacillus on 07 September 2009, 21:09
I'm hoping for your sake that your master cylinder is up to the task seeing you already have the tarox up front.
Title: Re: Rear brake upgrade
Post by: Hurdy on 07 September 2009, 21:53
you don't hang about with these upgrades do you!?  :shocked: :shocked:

You can't hang around in this game. Leave it too long and the weak link can bite you :shocked:

I'm hoping for your sake that your master cylinder is up to the task seeing you already have the tarox up front.

It should still be okay....If not...guess what my next mod will be :laugh:
Title: Re: Rear brake upgrade
Post by: Teutonic_Tamer on 08 September 2009, 11:35
I'm hoping for your sake that your master cylinder is up to the task seeing you already have the tarox up front.

It should still be okay....If not...guess what my next mod will be :laugh:

The rear caliper piston diameter for the R32/S3 rears is only 3mm more, so shouldn't really affect the master cyl.  The only effect that larger diameter pistons have is to give a slightly longer brake pedal - but this should hardly be noticed, and also be negated by the greater efficiency of the increased hydraulic advantage, and the larger diameter discs. :nerd:

And some of the pistons in the Tarox fronts are really very small!
Title: Re: Rear brake upgrade
Post by: Hurdy on 08 September 2009, 15:03
I'm hoping for your sake that your master cylinder is up to the task seeing you already have the tarox up front.

It should still be okay....If not...guess what my next mod will be :laugh:

The rear caliper piston diameter for the R32/S3 rears is only 3mm more, so shouldn't really affect the master cyl.  The only effect that larger diameter pistons have is to give a slightly longer brake pedal - but this should hardly be noticed, and also be negated by the greater efficiency of the increased hydraulic advantage, and the larger diameter discs. :nerd:

And some of the pistons in the Tarox fronts are really very small!

Yeah, I had the option of going for RS4 rears, but backed out when considering the pistons. The TAR-OX pistons are really weeny, so shouldn't mean an upgrade hopefully :cool:
Title: Re: Rear brake upgrade
Post by: Teutonic_Tamer on 10 September 2009, 08:38
Any further progress, John?
Title: Re: Rear brake upgrade
Post by: Hurdy on 11 September 2009, 00:19
Any further progress, John?

They are going on Monday afternoon Sean :smiley:

After bedding them in for a couple of hundred miles or so I'll give them a good workout and report back on whether they have "tidied up" the feel of the rear under heavy braking and trail braking :cool:
Title: Re: Rear brake upgrade
Post by: Hurdy on 14 September 2009, 22:56
Upgraded the rear brakes this afternoon. Managed to get hold of some S3 rears - not painted yet and quite like the look of the black with the wheels anyway at this point.

Fitted straight on, but unfortunately the S3 disc guards wouldn't fit, so I've ordered some Cupra ones that will.

First opinion is that the rear is a lot more stable under hard braking. The extra grip of the R888's along with the braking power of the TAROX 10 pots meant that the rear became under braked power-wise and was trying to overtake the front-end/squirm wide on hard use. Now the rears seem a much better balanced.  :cool:

Pics not great, but you get the idea.

(http://i156.photobucket.com/albums/t8/hurdy_album/S3rearbrakes006.jpg)

(http://i156.photobucket.com/albums/t8/hurdy_album/S3rearbrakes005.jpg)
Title: Re: Rear brake upgrade
Post by: Teutonic_Tamer on 15 September 2009, 08:25
Great stuff John - keep 'em black though. :afro:

So what is the difference between the S3 and the Cupra sh!t splash shields? :undecided:

And are you gonna tweak the bias in the VCDS settings? :wink:
Title: Re: Rear brake upgrade
Post by: Hurdy on 15 September 2009, 13:33
Great stuff John - keep 'em black though. :afro:

So what is the difference between the S3 and the Cupra sh!t splash shields? :undecided:

And are you gonna tweak the bias in the VCDS settings? :wink:

The S3 splash shields have a different mounting arrangement to the Cupra. The S3 ones have 4 mounting points and you can't even get 2 mounting points to match up and keep the orientation correct for the discs. The Cupra ones have the same mounting points as the ED30. Must be something to do with the haldex/hub on the S3?!?

I'd rather leave the bias as it is. The TAROX fronts take slightly more fluid than stock brakes and now the rears do too, so hopefully the bias is closer to an OEM % split than it was before the rear upgrade. :smiley:
Title: Re: Rear brake upgrade
Post by: bmx on 19 September 2009, 07:04
Quote

The S3 splash shields have a different mounting arrangement to the Cupra. The S3 ones have 4 mounting points and you can't even get 2 mounting points to match up and keep the orientation correct for the discs. The Cupra ones have the same mounting points as the ED30. Must be something to do with the haldex/hub on the S3?!?


i have the rear s3 brakes and i fitted the shields, my s3 shields only have 3 holes, the top 2 lign up and the bottom one just needs the hole ovaling with a drill bit and then flatterning with a pair of pligers, it takes about a minute to do.even touched them up with some matt black paint.  plus point to the s3 shield is it goes over the hub flange without having to cut it or worse still remove the flange.