big brakes

[RedRobin]

As an aside, don't Brembo own AP Racing now?

Yup, but the two companies work completely separately - with AP being primarily responsible for motorsport specific products, whereas Brembo still specialise in all flavours of road cars, along with a truely dedicated 'aftermarket' upgrade programme, the latter of which is not officially in APs remit.

....That's right [Wow! T_T and I agreeing about a corporate subject - Must be a first! ]. Brembo saw the sense in allowing AP Racing to keep their long established (remember Lockheed?) pedigree brand in the world of motorsport and high performance applications.

[RedRobin]

Upgrading the front brakes is probably my next mod, as I find the OEM brakes on the GTI quite prone to fade.

I know you said you didn't want the AP Racing setup but thought I would add that the bloke who lives opposite my in-laws works for AP racing and used to run the AP 4 pot system on his MK5 Golf. For what it's worth, he told me not to bother with the 6 pot setup as the incremental performance versus the 4 pot setup is not noticeable unless you do LOTS of track work. The AP setup should fit under the standard GTI wheels so long as you have the 18"'s. You can download the technical drawings from the AP site and print them out real-size on a plotter to check them against the car. Also the AP's are available in red, should you want to keep the car looking relatively stock. I wasn't aware of the cracking issue on these though............

^^^^ Exactly what AP's Senior Race Engineer, Pete Collen, advised me - That 4-pots and fronts only were absolutely fine for fast road use and that the Golf did about 85% of its braking on the front. I found them awesome on The Ring though my rear end did get twitchy a few times!

[RedRobin]

AP calipers are known to crack around the bleed nipple.  Not an issue for big race teams who just fit a fresh caliper on a couple of times a season - but for a private owner . . . 

....I'm not for a moment saying you're wrong - Only that, so far, touch wood, I've had no problems with my nipples (on my AP calipers!) after about 45k miles and now on my second set of both AP discs and DS2500 pads.

Ta for the tip off - I'll have that checked next time I'm at VWR.

Re VWR's brakes - apart from being very expensive, they do snatch but have totally gobsmacking stopping power! VWR are apparently working on a cheaper and more road friendly version.

[RedRobin]

AP calipers are known to crack around the bleed nipple.  Not an issue for big race teams who just fit a fresh caliper on a couple of times a season - but for a private owner . . . 

....I'm not for a moment saying you're wrong - Only that, so far, touch wood, I've had no problems with my nipples (on my AP calipers!) after about 45k miles and now on my second set of both AP discs and DS2500 pads.

Ta for the tip off - I'll have my nipples checked by one of the girls next time I'm at VWR.

Re VWR's brakes - apart from being very expensive, they do snatch but have totally gobsmacking stopping power! VWR are apparently working on a cheaper and more road friendly version.

[jaydubveedub]

Are there any potentially adverse affects on the rest of the 'stock' OEM brake system if you uprate the front discs an calipers?

[RedRobin]

Are there any potentially adverse affects on the rest of the 'stock' OEM brake system if you uprate the front discs an calipers?

....No (if I've understood your question correctly) - The sensors etc will continue to smartly react to whatever is going on. However, some big brake kits such as AP's no longer activate the car's pad wear system. But visual pad inspection is more reliable anyway.

If you mix and match brake components - Such as simply changing to better aftermarket pads and ss hoses and fluid etc - The feel of the brakes will improve but improvements will be limited by the oem disc [So I am led to understand].

VAG factory cars are well known for their relatively soft brake pedal feel. The pedal response from a good aftermarket brake kit adds to your confidence in that extra stopping power. Unless I'm being closely chased into a roundabout by a much higher performance car driven by someone who knows what they are doing (in which case I make sure to let him pass at the first safe opportunity), I find that my brakes allow me to apply them late so I'm slow into the corner and then the Quaife helps my traction to power out......Et voila, they are very small in my rear view mirror and they don't tailgate me again!

BUT! Remember that your only points of contact with the road surface are 4 patches each only the size of a CD, so in other words your tyres are critical!

[Teutonic_Tamer]

Sooooo, does anyone know if any other PQ35 platform car had 310x22 at the rears, but with just a plain anodised silver caliper, rather than the blue R32 or black S3 affairs, and preferably with the 41mm dia piston, rather than the GTIs standard 38mm dia.

Doesnt the 3.2 A3 have the same setup as the S3 but the calipers are unpainted?

Thanks, but I've gone off the OEM 345mm S3/R32/A3q route - they are just too heavy.  Reducing unsprung mass plays a massive advantage to general handling too - which is why I'm seriously considering ceramics. 

[Teutonic_Tamer]

Upgrading the front brakes is probably my next mod, as I find the OEM brakes on the GTI quite prone to fade.

I know you said you didn't want the AP Racing setup but thought I would add that the bloke who lives opposite my in-laws works for AP racing and used to run the AP 4 pot system on his MK5 Golf. For what it's worth, he told me not to bother with the 6 pot setup as the incremental performance versus the 4 pot setup is not noticeable unless you do LOTS of track work. The AP setup should fit under the standard GTI wheels so long as you have the 18"'s. You can download the technical drawings from the AP site and print them out real-size on a plotter to check them against the car. Also the AP's are available in red, should you want to keep the car looking relatively stock. I wasn't aware of the cracking issue on these though............

^^^^ Exactly what AP's Senior Race Engineer, Pete Collen, advised me - That 4-pots and fronts only were absolutely fine for fast road use and that the Golf did about 85% of its braking on the front. I found them awesome on The Ring though my rear end did get twitchy a few times!

That is a fundamental example of incorrect brake bias, because the rear brakes on the Golf need to work MUCH more than the '15%' - and this is borne out by the way the rear suspension is set up.  The Golf 5, just like the Mk4, and many similar modern road cars - have a much greater rearwards bias in the brakes - and whilst the fronts may actually do most of the actual 'braking', the rears play a massive part in the stability whilst braking.  Why do you think that some cars are now coming with larger REAR discs than fronts. 

[Teutonic_Tamer]

AP calipers are known to crack around the bleed nipple.  Not an issue for big race teams who just fit a fresh caliper on a couple of times a season - but for a private owner . . . 

....I'm not for a moment saying you're wrong - Only that, so far, touch wood, I've had no problems with my nipples (on my AP calipers!) after about 45k miles and now on my second set of both AP discs and DS2500 pads.

Ta for the tip off - I'll have that checked next time I'm at VWR.

How often have you had the brake fluid changed?  I just think that as an earlier poster said, it seems to be as a result of more frequent fluid changes by the race teams.  But if you are into track days on a road car, and need to change the fluid regularly, then it just might become an 'issue'. 

Re VWR's brakes - apart from being very expensive, they do snatch but have totally gobsmacking stopping power! VWR are apparently working on a cheaper and more road friendly version.

Oh yus - the VWR brakes have mighty stopping power, there is no doubt about that!    Cost-wise, well that really isn't a deciding factor for me, so it wouldn't have mattered if they were £500 or £2500.  The real big issue is that the SWMBO isn't very 'delicate' with the brake pedal  - so the brakes must have much greater progression than what VWR were offering, hence why I have to rule them out.  But if you say they are developing some newer ones - are they ready yet? 

As an aside, though, I was mighty impressed by their on-track racing operations, and have to say that Sam is a really nice, top bloke.

[Teutonic_Tamer]

Are there any potentially adverse affects on the rest of the 'stock' OEM brake system if you uprate the front discs an calipers?

Yes.  It can affect the front to rear bias.  An this is all controled by the software 'map' within the ABS/ESP unit - although there is a tweak - but this is an un-authorised setting, so the stealers wont get involved.  Sadly, virtually all the aftermarket big brake vendors seem not to get involved in this either.