AHA! Bristol as an airplane company would have been far too advanced to consider chain drive to drive the rear axle. Much too "19th century". Had to have been some Frazer Nash influence in there. Thanks for this most rare and unusual donation. Ettore
There were several AU copycats at that time, with much smaller engines, usually built in garden sheds. I think there was a car called the Multi Union, can't remember the details about it; and others. I'm still amazed that a car that seemingly advanced would have chain drive - but it worked well, so why change? Ettore
I bought a Magazine called Motor-Klassik here in Germany, and there is a guy in it who built a car with a American-Lafrance chassic, a selfmade body and a 47(!) Liter BMW aircraft V12. This car has chaindrive too, and the guy who built it sais that you can still make a burnout at a speed of 100 miles an hour. I can post pictures of tis crazy machine.