Rear Disk Conversion - What do I need?

[isaidthephil]

Hi All,

During my build I may possibly do a rear disk conversion, although I can't decide as I like the simplicity of drums.

If I was to do this can anybody tell me what exactly I will need and tell me of any real benefits?

Thanks

[ChrisPears]

Spindles, caliper carriers, calipers, discs, pads, disc retaining screws, flexi hoses (mk2 golf gti ones will do), 16v scirocco handbrake cables, backing plates (optional). I changed the brake proportioning valves on the master cylinder for the 16v ones too, but not sure if its strictly necessary.

[Nate]

any real benefits?

Unless its going on a track, its mainly just aesthetics. Rear brakes do very little of the stopping for normal road driving.

[GTXTRA]

No need - and I've got a 16v set up on a car.

Really.

[isaidthephil]

Nice one cheers guys.

I'm not going to bother then if it doesn't make much of a difference. I am running a 16v in my car and tbh it stops ok atm, I may just fit some bigger front brakes.

[mark1gls]

The main problem with drums is the auto adjuster does not always work very well, with disc the adjuster is better so the brakes feel better.
You can poke a screw driver through a wheel bolt hole and get someone to press the brake pedal while you push down on the adjuster, if you shine a torch in the hole you can see the adjuster.

[Nate]

^^ do this, it makes a huge difference

[whiteshark]

If your running standard brakes with a sixteen valve, upgrade the front brakes before you touch the rears. On my old car a 1.8 GTII, I put 256 discs on the front. Made a world of difference. I then put on discs on the rear, for me any extra stopping power is good and it did make a difference. The reason I put discs on the rear was mainly due to the MOT centres over in N.Ireland. You fail the MOT with even a small brake imbalance. I found that wheel cylinders in the rear drums don't last that long. Yes its easy to balance the brakes but you fail due to foot pressure and the wheel cylinders playing up. For me rear discs and calipers are quicker to balance and repair. On my last rear disc conversion for the 16v I bought a rear axle with the calipers discs fitted and changed the fronts to 256mm at the same time. I thought it would be an easy fix, bolt on bolt off. The 16v sciroccco handbrake cables did not fit and Mk4 Golf cables with the plastic housings trimmed were used instead. The master cylinder had to be replaced with a 22mm due to lack of pressure and I had to get a late MK2 GTI 16v servo to get the correct pressure as on the first attempt the servo did not release the pressure fast enough and my brakes locked 2minutes away from the MOT centre. I had to wait 45 minutes before the pressure dropped and missed my appointment and drove home in a low gear only using the handbrake. The hills were fun. The joys of playing with brakes. So depending on what type of calipers and discs you fit to the rear you might have to change the servo and master cylinder to get it all to work really well. So If I were you get the fronts upgraded first, never mind the rears.

[treefingers]

This is good to hear. I need to upgrade my brakes to match the 1.8t I'm putting in and I've been wondering a lot about converting the rears to discs.. I'm not bothered about aesthetics so I hope refurbishing/buying new drums will be sufficient. I'm not going insane power but I'm wondering if 256 front and a mk2 16v servo and 22mm master cylinder will be enough. What's the next step up, 280mm?

[isaidthephil]

I need to check my front brakes tbh as i have a funny feeling they have already been upgraded. I borrowed some 15" alloys off my mate when I was refurbing my G60's which for some reason caught the callipers on the front. I thought it was weird as my mate had the wheels on his mk2 GTI with no problems.

I will definitely look into putting something bigger up front through as the motor will be pushing 180 - 200bhp later next year =s

[Nate]

I need to check my front brakes tbh as i have a funny feeling they have already been upgraded. I borrowed some 15" alloys off my mate when I was refurbing my G60's which for some reason caught the callipers on the front. I thought it was weird as my mate had the wheels on his mk2 GTI with no problems.

when i was young and daft, i took a grinder to the calipers on one of my astras, as the (genuine vaux) alloys i'd just bought were catching them. only had to take a mil or so off. never worked out why, as the wheels came from the same model and spec car. very weird