T25 rear disc upgrade

sven · Jedi Guardian Joined: 27 Dec 2006 Posts: 814

When I was going to bleed the brakes I broke one of the crappy bleeder vents. It will take pretty much time to fix it so I decided to go for a brake upgrade directly.

The discs are rear discs from a VW Sharan.
The calipers are from a VW Golf -92 and onwards.
The short rubber hose is an Audi part.

I did a mistake. I bought a pair of Passat calipers long time ago to upgrade the brakes on a bay window I once had. Now when I decided to do the vanagon I realized that the connector for the brake fluid was pointing directly towards the axle AND it was suppose to be connected with a banjo coupling. It would never work, even if I grinded away material. So the conclusion is, don't use Passat calipers!
Next Oh-no was when I went and bought a new pair of calipers for a Golf - only to find out when I was back home that the new calipers where delivered withouth the mounting bracket...
Anyway, the brackets are luckily the same on the Passat so I grabbed them from the old stoppers.

I've been really careful to write all the part numbers down. But they are all related to a Scandivavian parts store. If you happen to be in Sweden/Norway/Finland and would like to do the same I can provide the item list needed.

So...
Cutting the hubs down to 145 mm dia.

Back to the vanagon

This is the Golf-caliper and it fits like a glove!

I made a 6 mm thick adapter plate and it's almost perfect. 5 mm would be absolutely perfect but too thin though. I made the adapter from a steel plate I already had, a few mm wider and all three bolts at the bottom would fit. Two will be enough anyway.

I centered the disc with a couple of wheel nuts and drilled two new locking/centering screws.

Tried 14 " rims just to see if there's any clearance. It does work but it's soooooo tight...

Someone mentioned that he had got water in the hand brake cable and it got freezin stuck when it was cold, To avoid the same i made a rubber cover out of a bicycle tube and glue. I also filled the rubber with grease.

Everything done!

wolfsbitz · Wannabe Joined: 04 Nov 2011 Posts: 1 Location: SOMERSET

Good work, after just putting audi s2 twin pot calipers on the front of my van i am now collecting the parts to do the same rear disc conversion as this, i have golf gti rear calipers and carriers, sharan rear discs and machined some backing plates, was just wondering about the pipe work. What flexi pipes did you use? Also do the standard t25 handbrake cables reach or did you adapt them? cheers Happy

sven · Jedi Guardian Joined: 27 Dec 2006 Posts: 814

The standard wires are working, but you have to reroute them a bit and add an 80 mm extender in the front end. I also added the external return spring from the Passat -00 calipers, it seems that the bus wires are too restistant with the result of the e-brake arms not going back enough. With the extra springs added there's no problem at all and I can lock up the wheels anytime.

http://switchamotor.blogspot.com/search/label/Rear%20brake%20upgrade

Superleggo · Posted: Mon Apr 16, 2012 10:51 pm Post subject: early bay

Are the Vanagon rear hubs the same as those on an early Bay window? Do you know if the offsets are the same?

From the rear bay drum mounting bracket to the front of the hubs is 57mm. The Sharan discs are 46mm thick so with disc flange being about 6mm thick the gap between the disc and the mounting bracket must be about 17mm.

On the Golf caliper carriers the distance is 32mm to the disc edge from the machined surface on the carrier. so the offset would be wrong unless you mounted the carriers on the unmachined side.

It is difficult to see from your pictures which side they are mounted on the caliper carrier. Did you machine the carrier or are the golf and pssat carriers different offsets?

T2 turbo · Padawan Joined: 19 Jan 2009 Posts: 89

You'll need to fit late bay hubs with the smaller pcd, i've got a template
Somewhere for the caliper brackets if you fancy doing this,
I used 190e merc front discs but used astra rear calipers when i did this,
I've got all the info on my thread on early bay from before i did
The scooby conversion.

Superleggo · Posted: Tue Apr 17, 2012 7:51 am Post subject:

I think my rear hubs are the later ones s it is a 71 bay and think they changed at 70? so they are 5 x 112mm

Audi A6 hose is suggested as a good sit for the caliper I assume it is a rear hose not a front one?

Superleggo · Posted: Sun Apr 22, 2012 10:17 pm Post subject: offset?

just made up a 6mm bracket and fitted it to the rear hub on my bay. But with sharran discs the offset(46mm) is all wrong for my golf calipers. It is reasonably close if you mount the carriers on the unmachinerd side, but on the machined side it appears 20mm or so out. I plan to shim the disc forward on a temporary basis to work out the offset and then make some z shaped caliper mountings. Also the Bay mountings appear to be rotated by 20 deg or so in comparison to those on the T25. Does not look as simple for my Bay.

I will post some photos tomorrow.

T2 turbo · Padawan Joined: 19 Jan 2009 Posts: 89

http://forum.earlybay.com/viewtopic.php?f=2&t=8148&start=80
Follow this link its how i did mine the first time.