Vintage Thing No.138 - GN

I'll be looking out for this device again! Driven by Duncan Pittaway, it appeared in the 2014 Land's End  Trial running as a 3400cc GN.

Combining the looks of a Brescia Bugatti with those a Shelsley special it sounded bloody brilliant, too!

Binky told me the barrels and heads came off a WWI aero engine but that's all I've learnt about it so far. My immediate thought was what sort of crankcase does it use?
 

Transmission is of the GN/Frazer Nash school. Duncan's in his TVR 4000 in the Exeter Trial but I hope to catch up with him and quiz him about this device.