interesting engine, guess this was Irvines attempt at a car engine , excellent engine data on it 4000 to 30000 rpm 0.9HP, they never got any market penetration so they machined down
the top the of the car head for aircraft use, made a extended spinner nut so a prop could be mounted I think very few made picked up from Just Engines UK around 2005
I do have the tuned pipe for it also will do a serious bench test with a few props for a 15 an 8x4 or 5 as a start
the Diesel head was made by A.J.Coholic will keep the group posted on the results it is a twin BB. do not believe many around martin

Irvine 15XR