RE: Can I temporarily use a 11 x 7 prom on my Magnum GP 40?
How long are you actually going to have to wait for the 10x6's to get there? The plane will fly differently with the 11x7, and not in a good way. The engine will lug and not get into the RPM where it makes decent horsepower. I'll say stick with the combination that's been working for you and be patient until your props come in.