Hi Martin
I can answer this.
See attached 3 photos of a MVVS D7. Thay were tha same vintage as the Super Tigre G20 deisels.
My only experience with both engines were as racing engines. I used a D& in Australian Goodyear racing for a few years and if anything.
I got better results with it than the Suer Tigre's.
I also agree that both engines make great sport engines.
Whilst we would run the G20's and D7's in TR Rat Race and Goodyear model on 7x6, 7x7 or 7x8 glass props running hard,
using them as a sports engine on larger props, they should last a lifetime on the right fuel.
Hope this helps

Fredo
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