Rear Brakes

The standard Jaguar rear brakes are functional but not that much to look at and there is not a lot you can do to make them look at home on a custom vehicle other than paint or plate them.  Even when you do that the hand brake calipers just look untidy.

So I decided that I would would try and fit some aftermarket brakes to neaten everything up.  As it happens someone else had already thought the same thing and had devised a way of mounting some Wilwood Calipers and Wilwood handbrake Calipers to the rear axle.  The person who had already worked this out is Mike Bontoft of CWI (Concours West Industries).  Mike is an Ex Pat who now lives in the US.  There is not much if anything that Mike doesn't know about the Jaguar Rear Axle. 

Here are the component parts as supplied by CWI, there are two custom manufactured mounting brackets, Wilwood brake and handbrake calipers and associated hardware.

 

 

 

 

 

 

In addition to the new Calipers I needed to replace the Discs as they were badly worn and one of them was cracked.  There are a number of aftermarket options including vented upgrades but I decided to go with the solid discs but grooved and dimpled (Blind Drilled) as made by EBC. 

You can see the new discs here:  

Note the Dimples (blind drillings) and grooves.  The dimples are supposed to provide improved braking but are not susceptible to cracking as with cross drilled Discs.  I am not sure how much of a problem that really is.  I guess I will find out as the front discs are cross drilled and vented.

 

Because Jaguar used a couple of different designs of output shaft bearing housings it is necessary to modify the later one to fit the brake mounting brackets.  You have to remove the original mounting lugs that secured the original calipers and also machine down the outside face flat to bolt the new brake bracket against using the original mounting points.

Here you can see the bearing housings after they have been machined down, I have also removed the original caliper mountings.  Mike of CWI does all of this an a CNC Mill, but as I do not have access to one I had the face turned off in a lathe.  I cut the old caliper mounting lugs off simply with an angle grinder.

 

There was one little job that I had to do to the brake caliper mounting brackets. I had to file a very slight chamfer to the inner edge.  This is because I left a very small radius (approx 2mm) at the inner edge of the machined face of the bearing housings.  When I came to try the brackets in place I realised that they were very tight to the inner edge and had a 90 degree edge on them, which meant that they didn't sit flat when you lined the mounting holes up.  Rather than re-machine the bearing housings, it was easy to simply file a chamfer to the brackets as can be seen below.

 

 

I decided after sorting out the internal chamfer that I needed to put a finish on the mounting brackets as the way they were supplied was just bead blasted.  So if I put no protective coating on them they would soon start to show the effects of oxidisation.  When Mike supplies them usually they are provided as black Anodised, but as he made them at short notice for me there wasn't time to anodise them before I picked them up.

So I decided to get them black anodised myself, only issue I had was that they were fitted with some threaded inserts to mount the calipers like Hank Bushes.  So I had to remove these first as the anodising process would attack the steel.  So after knocking them out I got the anodising done at a local metal treatment shop then refitted the inserts.

Here are the finished anodised brackets ready for assembly.

 

 

The brake mounting brackets bolt directly to the modified output shaft bearing housings.  With the standard brake setup the Discs usually have 1 shim behind them to space them central in the calipers.  However with the brake setup I am using, this does not seem to be the case.  I mailed Mike of CWI to get confirmation of the setup.  It looks like the brackets are machined to fit a variety of axles etc.  With my setup the brake disc not only needs a good bit of spacing but the Calipers actually need a fairly large adjustment from the brackets too to get them to line up correctly.

Here are the Caliper mounting brackets in place on the output shaft bearing housings.

 

 

Here you can see a close up view of the caliper mounting.  This shows the 4 washers that I have put between the mounting bracket and the caliper.  Even with the 4 washers the disc still needs a couple of shims behind them and I think that I may have to space the calipers yet more to allow the necessary Camber adjustment. 

Here you can see the calipers and discs in place from the rear and the side view.

 

Here you can see the Parking brake (Safety brake) calipers in place.

 

 

When I bolted up the Calipers, it was clear that I would have to do something with the Diff cover as the fins fouled where the NPT fittings connect.  Here you can see my chosen solution.  I just cut the fins out of the way to make the necessary clearance.