Thread: Salisbury Disc Brake conversion

Lots of good questions!

I will try and answer based on what I have experience with.

110 front rotors should work but you will need to adjust the spacing of the caliper, I've only done it with Disco stuff mainly because the vast majority of these conversions (over here) are done on Disco's and D-90's.

1994 and up Defender rear calipers should work straight up with Defender rear rotors No adjustment to the spacing "should" be required. I've only just obtained my first set of rear 110 calipers and have not had any time to "fiddle" these calipers are virtually unobtainium in the states as a wrecking yard item because no 110's with rear disc's ever came to North America.
In theory they should work better but I'll have to swap them out to tell for sure.

You can use a 110 Front hub but you will find that the bearing spacing is too wide. You can add a spacer behind the outer wheel bearing race or you can add a ring under the outside edge of the outer wheel bearing on the stub, I did this and it was only 'OK" In the end I changed it.

1994 (1993ish for RRC) and up is indeed the point at which all things become the same but shorter. What we call the ABS hub and stub has narrower spacing at the wheel bearings and a shorter stub. From here on it become the standard for all Rovers that do not have unit bearings.

The bolt spacing is different for front rotors, that said the factory bracket couldn't be used but you could fab up some based on factory brackets with the bolt spacing for the front. I suspect that the master cylinder woudl really need to be upsized to make this work but i haven't actually measured the volume of the fronts compared to the rear.

For those that have fab skilz and want to make their own: I have a partial drawing of these brackets, I will finish it up and post it in a format all can use (probably not metric though ) give a few days and we'll see how far I can get with it.. It's a bit chilly in the shop and I'm a wuss..

Just completed my conversion yesterday.

I ended up with:
- D1 update rear calipers, discs, caliper mount bolts, and disc mounting bolts.
- Factory caliper mount brackets (FTC3306) but had to machine a combined total of approx 4mm off the mount faces for each bracket (3mm off the axle mount face, and 1mm off the caliper mount face)
- County front hubs
- Original county rear stub axles from drum rear
- Original county rear axles and drive flanges (longer axles than defenders).
- D1 or County front hub mud shields (the round one that the hub mount bolts go through)
- Shorter stub axle mount bolts as you remove 6 long ones, but need shorter ones since you don't refit the thick mud shield ring.

Other useful things I found along the way:
- Can't fit county front stubs on the rear as the rears locate around the outside of the axle flange, and the fronts locate on the inner diameter of the swivel.
- Can't use early D1 rear calipers as they have different mount bolt diameters.
- Can't use the original hub mud shield from the the drum hubs as they are too thick and the bolt heads foul on the disc mount bolts
- The County front disc mounting flange is slightly thicker than the D1 disc, so the bolts are slightly longer. Best to use the D1 disc mount bolts as the county ones bottom out on the plain bolt shank. It may be possible to use extra washers under the heads of the county ones, but you could run into clearance issues with the stub mounting bolts once the hub is fitted. I didn't test.
- Apart from the PITA of machining the mounting faces, I also found that the middle 2 holes in the caliper bracket didn't line up properly with the axle flange, and it was impossible to get the bolts in. I ended up drilling them straight through and fitting a nut on the inboard end of the bolt. The 2 end bolts in the bracket were installed normally into the threaded holes.
Not sure why the middle holes didn't line up as I haven't read of anyone else having that problem. Maybe it was the Britpart brackets????

If you want to do a disc conversion, then this is definitely the hardest way to do it (apart from also getting brackets fabricated from scratch).
I had accumulated a lot of the parts cheaply, but if you had to buy them all then unless you had a particular reason to keep your old axle it would be MUCH easier (and probably about the same cost) to just buy a decent defender disc rear from a wrecker and roll it under.

Steve