Miles Gemini.
Gipsy Queen,
The prototype G-AGOS was fitted with 2 Continental C-125-2 flat 6's at one time, and it was modified by the Mikes company at Woodley. How it flew I have no idea, and have not read any pilot reports on it. It had straight exhausts so was probably quite noisy.
The Gipsy Major powered ones were quite noisy as well as they also had straight exhausts. I was involved with a Jack Ried at Elstree in fitting his with an exhaust manifold from a Magister and adding the rearmost section of a Dove exhaust to it. It was a cone shape with lots of holes to release the exhast gas. Worked well and was a lot quieter. Not sure the ARB knew too much about it??
There was a Miles M.75 Aries that was a Gemini with 155hp Cirrus Major 111's, and a couple of Gemini 3A's were converted to that standard. I believe "Flight" magazine had one of them??? They had bigger fins to give better directional control with the extra power.
"Scion", I had forgotten about the Scion with its wonderful little Pobjoys, but there was also the Miles Aerovan which initially had 90hp Cirrus engines.
Speedbird 48.