# Converting to rear disc brakes on MK2



## 86vdub (Oct 10, 2003)

Well I kind of tried to search and didnt really find anything, but my car is a 1986 Golf and since the '85-'86 Gti had rear disc brakes, im wondering what all i would need to do this conversion. I know that they are 9.4 and that is what I want. I also wanted to change to stainless steel brake lines, i would have the bentley manual, I am just wondering if this is too big of a job. 
Here are a few other questions that confuse me:
Would i have to mess with the metal brake lines under the car?
I can use the 20mm master cylinder right? 
I wouldnt have to get the rear beam with the p-valve on it would I, and if so, is this a hard job?
Also, could you please be specific with the parts that i need, just to make things easier for me, if not, thats alright.


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## Racer_X (Jul 14, 2002)

*Re: Converting to rear disc brakes on MK2 (86vdub)*


_Quote, originally posted by *86vdub* »_Well I kind of tried to search and didnt really find anything, but my car is a 1986 Golf and since the '85-'86 Gti had rear disc brakes, im wondering what all i would need to do this conversion. I know that they are 9.4 and that is what I want. I also wanted to change to stainless steel brake lines, i would have the bentley manual, I am just wondering if this is too big of a job. 
Here are a few other questions that confuse me:
Would i have to mess with the metal brake lines under the car?
Maybe, maybe not. I think you probably will have to make a change there, though.
_Quote, originally posted by *86vdub* »_
I can use the 20mm master cylinder right? 
Yes, your current master cylinder will work fine with the stock front brakes and rear discs.
_Quote, originally posted by *86vdub* »_
I wouldnt have to get the rear beam with the p-valve on it would I, and if so, is this a hard job?
You do need the load sensing regulator. But you should be able to bolt it up to your rear beam. The actuator are bolts to the axle beam. The mounting holes should be on your beam.

_Quote, originally posted by *86vdub* »_Also, could you please be specific with the parts that i need, just to make things easier for me, if not, thats alright.

You need the brake rotors, calipers, caliper carriers and spindles at the rear. You also need the load sensing regulator. You have to remove the current regulator or prop valves. Plumbing is directly from the master cylinder to the load sensing regulator, then from there through to the calipers. There is a flex line from the body to the front of the trailing arms, and another flex line from the hard line on the trailing arm to the caliper. Make sure there are no proportioning valves in the master cylinder, and no residual pressure valves in the lines between the master cylinder and the rear of the car.
You will probably also want to get the GTI rear springs, and you might want the rear beam because it has a stiffer stabilizer bar. The disc brakes are 6 1/2 pounds heavier per wheel than the drums. The stiffer springs and stiffer stabilizer bar will help control the extra unsprung weight. If you already have aftermarket springs and/or stabilizer bars, you might want to upgrade them to something a bit stiffer. 
If you want to know what the car will handle like with rear discs, bolt a 5 pound weight to each lower shock bolt and drive it for a week. If you don't like the handling with the 5 pound weights, you won't like 6 1/2 pounds of extra weight from the brake calipers.


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## machschnelGTI (Jun 28, 2004)

*Re: Converting to rear disc brakes on MK2 (Racer_X)*

I've got a couple rear disc setups if you haven't bought it yet. I have spindles, calipers, caliper brackets, used rotors, used wheel bearings, backing plates, dust caps, and a used set or rear stainless braided lines for $160. I can also get you rebuilt calipers instead or new rotors if you'd like.


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## onedub resurection (Jun 23, 2004)

*Re: Converting to rear disc brakes on MK2 (machschnelGTI)*

im converting from drums to discs on my 91 golf gl. so far i have the discs,pads,calipers & carriers, & will be getting the ebrake cables. i need the spindles,backing plates, steel braided lines just for the rears. anyone have these parts?


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## HilF (Jan 10, 2004)

*Re: Converting to rear disc brakes on MK2 (onedub resurection)*

i have spindles and backingplates (bent somewhat)


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## onedub resurection (Jun 23, 2004)

*Re: Converting to rear disc brakes on MK2 (onedub resurection)*









brakes going on this. help me finish this damn never ending project


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## vwa2driver (Jul 15, 2003)

*Re: Converting to rear disc brakes on MK2 (onedub resurection)*

I'm glad i found this forum, I have an 89' Jetta coupe and I want to convert to disc brakes off my 87' GTI 16v. I'm trying to do a complete swap, turning my 8v jetta coupe (auto) into a 16v (5-speed). I've broken down the entire GTI 16v except for the rear disc (which I have never done before). If anyone has any extra advice I would greatly appreciate it....Thanks...vwa2driver


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## Ricanchef (Dec 13, 2001)

*Re: Converting to rear disc brakes on MK2 (vwa2driver)*

I am almost doing the same except for the engine. i have a gli with blown head gasket so i put the trpohy recaros in my golf coupe. going to do a complete brake swap hopefully this weekend and probably in a few months do the tranny conversion. I have a question about the mster clyinder if i am going to put the 16v 10.1" front on my 8v would i need the 16v master clynider???


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## vwa2driver (Jul 15, 2003)

*Re: Converting to rear disc brakes on MK2 (Ricanchef)*

I would say, yes. You said you have a 91' Jetta, I think it would have come with 9.4" rotors, yes even the 16v's. I upgraded my 16v GTI to 10.1" brakes off a 93' Golf GL. I changed rotors, calibers, carriers and spindles. I decided to up-grade the master cylinder as well. I'm glad I did, because now I'm going to 11' brakes off a Corrado G60. All I have to do is change the rotors and calibers/carriers. I've got Zimmerman cross drilled rotors and G60 calibers/carriers. They are not that expensive and only make it better...I believe it is a 22mm master cylinder....


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## vwa2driver (Jul 15, 2003)

*Re: Converting to rear disc brakes on MK2 (vwa2driver)*

Well I don't know where I got 91' Jetta from, but anyway they all came with the 9.4" front dics.


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