26x8 might be pushing it for that engine but I don't have any facts to back that (I can only extrapolate from other props). I don't know of anyone running that large of diameter to tell you for sure. They are happier near 7000 RPM but you could run them at 6500. I run a Xoar 22x8 at 7400RPM on stock exhaust on 88" 17.5 pound aerobats and it's incredible power. 24x6 might be near 6900-7000. It's very possible that a 26x6 could turn in the range you stated but from my experience the engine is happier near 7k. For the type of flying you will do with that plane compared to my intense aerobatic flying, it might be just fine.