here comes trouble:
Got it! 1960 BRM.
Found one on Google images after asking on another forum. I`m not clever enough to put the picture on here, sorry.
Still dont know how it stops the car, when the brake doesnt appear to be connected to a wheel or axle
It is an ingenious idea, a single disc brake bolted onto a transaxle! You can see the drive shafts and when the brake is applied it will slow down the mainshaft
Trivial fact, both (ERA) BRM and Pilbeam were built in Louth 
milodon:
Silver_Surfer:
http://www.voith.com/en/products-services/power-transmission/retarders-trucks-10263.htmlHad the variable one in my Scania, great piece of kit, saves loads of brake wear on the discs and is very relaxing to use particularly if you tend to crack on and brake a bit later than you should from time to time. They are a couple of grand I think to spec on a new wagon which is why most don’t go for them but over the whole life of the wagon, this I would say is paid back with fewer discs and pads being used. If I ever buy another new wagon, i’d spec it.
I had 60% of the factory-fitted brakepads left on my scania when it had done 580 tkms - thanks to the retarder, but then again the tyres on the driveaxle only lasted 225tkms as opposed to 300 on non-retarder equipped trucks doing the same work.
There must have been some tyre life saving on the steers though.
