.: Brakes - Custom 9.25" vented Holden Camira setup

One of the unique things on my Moke is the brakes. You may have noticed in the previous photos the custom brake setup. The front brakes are a custom race brake setup for a Mini/Moke. They are Holden Camira rotors with Holden V8/VL turbo callipers. The rotor diameter is 9.25 inch and requires 13 inch rims which my Californian has. Two stud patterns are possible with this setup, either standard mini (4 by 101.6 PCD) or Morris 1100 (4 by 114.3 PCD). The CV's are new reconditioned units with new Cooper S tapered roller bearings. I have been told that this setup requires a master cylinder from an early model Mazda 323. From what I know, the Mazda 323 master cylinder has 2 circuits, one each for front and rear. I am also told that the rear proportioning valve may need to be adjusted or replaced with an aftermarket adjustable unit. I believe the unit required is an older model 323 that is cast steel with remote fluid reservoirs connected by hoses. If you have any more information on this setup or a recommended master cylinder then please let me know! Click here. I will likely need to adjust the cylinder sizes in the rear drums to the Cooper S type (5/8" versus the standard size of 3/4").
There is no need for a vacuum booster with this setup however I have one and will trial it once it is ready to go. I will need to have custom brake lines made up (Holden Commodore on one end and Mini on the other). Furthermore, the setup consists of original Mini drum brake bearing hubs with a custom mounting plate for the Holden Commodore callipers. The brake lines can be custom made easily by a brake specialist or motorsport workshop and from what I hear I just need to work out the length and tell them that I want Mini at one end and Commodore at the other and they'll make up braided lines!
For people interested in this setup, the Holden Camira's with vented discs were the JD and JE models 1984 - 1989. I am not certain if these are the same rotors as what I have.
Now here's an interesting piece of information for you all. The Californian Moke's actually came out with two 13" Sunrasia wheel derivatives. My Moke is one of the earlier Californians with four wheel drum brakes. The later models fitted with the 8.4" disc brakes actually had a different set of Sunrasia rims. The dish in these derivatives were offset further (the wheel base remains the same) to allow for the brake Callipers. As you would imagine, I had an interesting time fitting these puppies under the wheels. I actually ground the front part of the callipers down (the cooling fins) with an angle grinder to make them fit. The fact that I have 9.25" disc brakes spinning under a set of drum brake 13" wheels is a pretty awesome feat. The first couple of photos shows the original Calliper shape. The painted red callipers show the finished product after a nice filing to create a very smooth finish.

Update 20th November 2007: Only recently have I been delving into this a lot further. My understanding is now as follows with regard to this setup. The later (1977 on) Minis and Moke's actually had a larger dual circuit master cylinders (as mine currently has, refer to last picture on this page). A new one can be purchased here: http://www.minisport.com.au/prod604.htm. From what I know, this master cylinder has enough displacement to power these puppies. In addition, I will need to change my rear slave cylinders for the 5/8" ones to prevent rear lock ups. I have not yet tried this combo as my Moke is still in pieces however will update this when I do. I would appreciate any further feedback also Click here.

View of the Dual circuit master cylinder as fitted to the late model Mini's and Moke's (1977 on).

Update 19th January 2008: And so this project continues. I have just completed rebuilding the rear drum brakes. These now consist of mostly new parts (new 5/8" slave cylinders as fitted to the Cooper S mini's so as to prevent rear wheel lock ups with the new brakes, new brake linings, new drum holding screws). Fitting the Cooper S type cylinders were interesting as the locating pins appeared to be on the opposite side to those that were in the drums originally I simply redrilled the holes and all is ok on that front (see image below). I have also had the custom brake lines made for the rear. These are a braided line and have the standard Holden 10mm metric fitting on one end and the Moke fitting on the end connecting to the sub frame. I opted for the standard male type connector to the callipers with the single copper washer as the banjo type fitting created a large S in the line which wasn't to appealing and brought a risk of kinking. In addition, I have purchased a set of braided brake lines for the rear also just to follow suit.

 
Above: Zoom in and look at the top drum near the yellow cap (shot with two swing arms side-by-side). Notice the new elongated hole drilled for the locating pin next to the bleed nipple.

Update 22nd December 2008: Now that the Moke is pretty much finished I need to add some more details. I have since fitted my VH44 brake booster to complete the kit. The below images show the finished product:

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