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MG MGA - Does anyone recognise these brakes?
|I have recently acquired a Coupe that has had disc brakes fitted to the rear axle. Does anyone recognise what they are off? I am lead to believe they are from a Land Rover. Marking shows Dunlop 2 1/2" (or 2 1/4" hard to read).|
|To me they look like the later Jaguar Mk2 with the automatic slack adjusters.|
|That would fit with what I have been told a few times, that the Mk II Jag rear brakes can be used in an MGA - if you can find a set!|
|Jag MKII, XK150, XKE, or Rover P6 (2000) are the most common sources, some Alfa and other odd fittings,up to about 1966. Probably also other Rover (late P5) but not Land Rover. The wheel cylinders come in various sizes, interchangeable. But I think that 2 1/2" cylinders only fit the larger caliper, as fitted to big Jags front only. My memory says all cylinders up to 2 3/8 fit the smaller calipers. The rear cylinders would be expected to be noticeably smaller than the fronts, so if it has 2"+ rears they are probably wrong, and badly over-braked at the rear.|
I think the handbrake calipers had a lot of variation over time and original fitting. We had some parts that we never could identify positively, and I had all the above and MG TC/Deluxe to compare with.
|As FRM said, rear cylinders of 2" or over seem far too big.|
However, the master cylinder bore must also be considered.
The braking force is a ratio of the two bores (MC and Slave).
The Dunlop brakes on the mga twin cam are MC 7/8" the front slave is 2 1/8" and the rear slave is 1 1/2".
You should have a MC to slave ratio similar to the MGA Twin Cam.
The brakes in the photo seem to be the Jaguar type.
They have the centralizing spring on the handbrake levers and a hexagon nut which is loosened to change the handbrake pads.
Those two features are not on the MGA Twin Cam.
|M F Anderson|
|I cleaned off the numbers on the rear casting and it appears they are 2 1/4" (discs 10"). While these might be big, there are 11" ventilated discs on the front with 4 pot calipers to balance them. I not sure where these came form either - maybe these are Land Rover?|
Also there is a remote operated bias valve in the cabin alongside the drive tunnel for finer adjustment. Brakes seem pretty good to me.
|Another view or front brake caliper - any ideas from what they are off originally?|
|My knowledge runs out about the time of 4 pot calipers! But they look like Lockheed as they have the same pad springs as MGB. Must be some name/numbers on them?|
Somebody was serious, given the brakes and coilovers - what does this thing use for power?
|2 litre B series engine (bored and stroked) with a HRG Derrington head, twin DCOE 45 webers, etc.|
This thread was discussed between 11/09/2011 and 12/09/2011
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