big disc install

[aisekulic]

hi all, just wanted some feed back, im looking at installing new front discs for mk4 gti (2003). i want to put bigger ones on, need some advice on what would be a good option and how much i would be looking to pay... i want to install them myself.. so any advice would be helpful thanks.
i have 17in BBS wheels and stock suspension

[Manaz]

There are two mainstream options.

You *may* be able to get a set of 334mm R32 rotors (and associated calipers/carriers) under those wheels - it's a bit hit and miss with 17" wheels, they fit under some but not others.

The other option would be the 312mm front rotors (and calipers/carriers) from the Bora V6 4Motion. They'd almost certainly fit under the BBS wheels (nothing is guaranteed though, there was a case recently where some 17" wheels didn't fit over them for someone).

The R32 setup will cost you anything from $800 to $1000 second hand, and the replacement rotors aren't cheap - you can get a set in from overseas for about $500, but locally, VW wanted $600+ per side for the front rotors last I asked.

I sold my 312mm rotors and calipers/carriers for $300 to someone on here, he was having some issues with fitment on his car (it turned out the standard setup on the 1.6L Golfs is different to the GTI), if he hasn't resolved the issues he's having there, they may be an option for you (they may cost more than $300 though, the current owner cleaned them up a lot and may have also painted them)!

If you really want to upgrade, I'd look at the 312mm option - they're not too expensive, and they're a fair step up from the stock 288m setup. The 334mm option from the R32 has issues to contend with - do they fit under your wheels, they're expensive, the replacement rotors are expensive, they're also very heavy (and that can have an impact on steering), and unless you plan on tracking the car where the larger rotors can deal with the heat generated better than smaller ones, there's very little wrong with the 312mm option.

[Bizi]

ECS and other parts places may have a basic OEM-style converter 'kit' for bigger discs for your MkIV, as they do for the MkV:

http://www.ecstuning.com/Volkswagen-Jetta_V--TDI/Braking/Big_Brake_OEM/ES8707/

I am considering this for my Jetta V; as you can see, it is simply a kit to bolt on the new 312mm rotors (zinc coated, plain rotors) plus adaptor carrier brackets, with your existing calipers/pads.

The ECS site's MkIV section doesn't seem to have such a simple upgrade. http://www.ecstuning.com/Volkswagen-...--2.0/Braking/
If such a kit is available for MkIV, you might be able to get new rotors and keep your existing calipers/caps and not have to bleed your brakes, until pad replacement time (and maybe get the applicable bigger calipers during that time).

I've not read much about this option, but some people on golfmkv have commented that larger rotors are primarily for better heat dissipation (to hopefully reduce the risk of boiling your brake fluid when you really abuse the brakes ov per a short period of time).

[Manaz]

The bolt-on 312mm option on the Mk4 is only available for those with the 288mm front rotors apparently, which is the GTI, not sure what else.

gavs (on here) found this out the hard way. He's the one with the 312mm setup that he may want to offload.

[gavs]

Yes, I did indeed learn the hard way! Fortunately I was able to aquire some bearing housings that the calipers and carriers bolt directly onto, so now I just have to organise discs and pads......

[gavs]

See here.......

http://www.vwwatercooled.org.au/newforum/upload/showthread.php?t=41726