any one done a rear disc conversion on a mk1 golf?

hi all, i want to do a rear disc conversion just for looks really as i dont like rear drums, has  any one done this on hear and what parts would i need to source, is it straight forward? any replies would be great cheers timmy

Basically mk2 golf stub axles (as they hold the calipers) calipers, caliper carriers, discs , hose,  also need old scirrocco 16v h/ brake cables ( basically mk1 golf chassis with discs so cables fit) and either the gti rear pressure regulator or i believe the soft tops have different arrangement.I had to grind a little of the very back of rear beam away for clearance. This is all very simple and i would reccomend using more modern alloy calipers , c and r enterprises can also knock you a set of h/brake cables up for this.

thanks pal so i will need, mk1 stub axles, calipers could i use mk4 rear calipers, caliper carriers of a mk2 or mk4?,hose? what would this be for would i need to change the master brake cylinder? and scirrocco 16v h/brake cable, i have a cabriolet so i dont think i will need pressure reg, just the hose not sure where i will need to fit the hose to? thanks for the reply regards timmy

No the mk2 stub axles, yeah i believe the mk4 calipers bolt onto the mk2 carriers, the flexy hose is from the caliper (it moves ) to the solid brake line, its all very obvious once you have/see the parts. dont see why the master cylinder needs changing, there will be less fluid transfer than with badly adjusted drums.

If your budget allows you could use the polo/ibiza stub axles and hubs from a circa 2000 car, advantages being the stub axles and bearings are much stronger, bearings are in the hubs not the discs and are roller bearings so never need adjusting and makes disc and pad replacement easier, no picture unfortunately but this would give you everything but the cables and brake pipes http://cgi.ebay.co.uk/Polo-GTI-Rear-Axle-Disc-Brakes-6n-6n2-Conversion-/200586839273?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2eb3e844e9 just buy these flexi hoses http://cgi.ebay.co.uk/Golf-Mk2-Mk3-Goodridge-Hoses-Rear-Golf-mk4-Conversion-/330540644808?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item4cf5c1f9c8 and a pair of 16v rocco handbrake cables (c&r sell those as well) and your away if you already have a load valve on the axle

thanks alot lads very much appreciated, all seems very straight forward now i cant belive its as easy as that, great, regards timmy

yes mate not that bad really i fitted disc to my old cabby too!

1 more question can i use mk2 rear calipers, i cant see why not but best make sure before i start buying ?????

You can but best not to as the handbrake mechs are prone to siezing hence everyone uses the calipers with internal mechs (mk3, mk4, polo, ibiza etc) just watch which ones you buy as you dont want the rear being overbraked

cheers smokey, which calipers would you get?so its not over braking

Late mk2 do not have the handbrake seizing problem.

You will need
Disks
Pads
Inner and outer bearings and grease seal
Outer dust cover and new split pin assembly
Back plates
Inner dust covers
Caliper and carriers
Mk2 stub axles
Handbrake cables to suit, the original 16v Scirocco ones only fit properly in the hangers with early mk2 calipers, they are ok for the later ones but you have to hang them on modified hangers or cable ties. If you go for mk4 calipers then you will need the special C&R ones at £££
Spring clips to hold the handbrake cables to the calipers.
Flexible hoses, Goodridge 6 line kit or C&R ones for mk4 calipers.
Brackets to hold the caliper flexible hose to solid in place, modified mk2 items work.
Fluid
Either GTI rear compensator or inline late cabby pressure regulators, you must have one of these otherwise you will over brake the rear and be in danger of spinning out of control - also be aware that some earlier cars had what look like pressure regulators in the engine bay, they are simple one way valves !!
Brake pipe, ends and flaring tool for the new solid pieces from the flexible hoses above the axle.
Thread lock for the stub axle bolts and carrier bolts.

great reply there m8, i can crack on now and start buyin sum stuff, thanks

late MK3 are the ones to get. late MK2 DO still suffer from seizing handbrakes, the mech is the same as the early ones. i should know, both of mine started seizing up

the ones to get are the later style MK3 calipers without a spring on the outside, the early MK3s used MK2 calipers with the external spring. MK4 work fine but you need conversion cables, and they arnt any better than MK3s anyway so its just an extra expense over MK3s for no real advantage

lhasadreams said

…Either GTI rear compensator or inline late cabby pressure regulators, you must have one of these otherwise you will over brake the rear and be in danger of spinning out of control - also be aware that some earlier cars had what look like pressure regulators in the engine bay, they are simple one way valves !!

You wouldn't know which years came with those pressure regs would you?
Mines a 1990 and has some kind of valves fitted under the master cylinder. Wasn't sure what they were to be honest and if they would be needed for my 22mm master/9" servo and rear disc conversion.

Well I am not sure of the exact year change but EKTA shows this:

Rear Brake Pressure Regulator (load sensitive) 841 612 151   >> F 15-E-011 290   - This is the one connected to the rear axle

Brake Pressure Regulator (pressure sensitive) 533 612 151    F 15-E-011 291 >>  (also use 411 611 789) - You need two of these and they are screwed into the master cylinder

What is your chassis number ?

Something like
WVWZZZ15-E-011291

Where the dashes have letters in them that are not significant to work out which cars had them.

Are yours screwed into the master cylinder ?

You dont want to be using the valves which screw into the master cylinder unless they are the proper 16v scirocco ones (hard to find and 200 euros new from vw classics) reason being is the valves from a car with rear drums hold pressure which isnt something you want with rear discs, best bet is to either get adjustable bias valves as used in motorsport or to mount a load sensitive valve to the rear axle beam

Smokey, I have to disagree with you there, I did a lot of research on this before I converted the Mrs cabby Sportline.

The later cabby pressure sensitive regulators that screw into the master cylinder are the same as the 16V Scirocco ones, just checked again on ETKA and they are the same part numbers.

You are thinking of the check valves that were fitted between the master cylinder and front pipes in the engine bay on some tin top GTIs, they come as two pieces, part numbers 171 611 789 and 113 611 191.

I can confirm that the late cabby pressure regulators do not hold any residual pressure.

The valves are different and carry a different part number, 16v rocco valves 533 612 151 A, 1991 golf cabriolet 533 612 151, the amount of bias differs between the two types of valve, they carry different markings (i have both types here side by side) probably some good info on them on vortex but im too tired to go looking

Interesting, ETKA must be wrong then, on my version they have the same part number.
I wonder what the bias difference between them is ?
When doing this conversion I always use a 22mm master cylinder and 9" servo, along with the 256mm calipers/Audi Carriers.
The wifes car brakes very well and not a hint of over braking from the rear. It has passed 2 MOT's with this setup, so that leads me to think that the cabby pressure regulators work well with this setup.

Ever thought of running some pressure tests on the valves you have to really see what the difference is ?

Sure your not confusing standard scirocco valves for 16v ones on etka? the years the 16v was available it lists both on the same page and identifies the 16v ones as 16v, all the info is on vortex im just shattered but if you want to have a nose round and see if you can find it... if i can mock something up when i have some time spare i may test, btw apparently the old astra gte (mk1 i think) has usable valves very similar if not the same as the 16v rocco valves, from memory however you will need the valves from two cars as one is m10 and one is m12