Quick everybody, no fair googling, what was the ME108?

a 4 seat passenger plane. IIRC, it was Messersmit’s first comercial venture with an engine. Before that he designed gliders, I think. Not sure why anyone would want to put a Merlin in a Bf-109. The D/B was in some respects a better engine. I don’t think it had the HP at sea level the Merlin I did, but it had a 2 stage supercharger after mid ’39 ( E model) that was better then the single stage on the Merlin.
It’s a sure way to start a brawl in an English pub, but the 109 was a better fighter then the Spitfire.
The Army air corps did a lot of testing in late ’43 early ’44 of over a dozen different fighters. The only major advantage the Spit had was the Malcom hood, which allowed better SA thru increased visibility.
The 109 actually had a smaller turning radius from about 15,000 feet on up. That is with a test pilot under non-battle conditions. The Spit had a reputation of tighter turns because it would let the pilot know that he was losing lift, so the pilot could back off a little and keep the Spit at 9/10 or more. The 109 would not wobble or shudder so you didn’t know you had a problem until you were in a flat spin and falling. Not a good place to be in the middle of a dogfight. So the German pilots wouldn’t take the 109 much past 7 or 8 /10ths, which left the spit turning inside it.
An illustration of the difference between theory and the real world.

Here is the URL for one of the navy tests;

http://home.comcast.net/~markw4/index1.html

The USAAC did a bunch of other tests, but I havn’t been able to find them again. IIRC they are part of the U.S. ARMY CENTER OF MILITARY HISTORY;

http://www.history.army.mil/index.html

We went around for about 2 years at the UC Berkley “On War” site over the best Fighter of WW2. After 50 years, you would think passions would cool down. NOPE!