They will turn bigger props, but I found a caveat to that. You may have to go to wood props, as the plastic ones have too much inertia. My Enya .09-III TV was difficult to adjust the needle valve with an APC 7x4 prop. I went to wood, and it was a completely different animal. It put out quite a bit of thrust on older Top Flite wood 7x6, IMO give the sport plain bearing Schneurles a run for their money. I haven't tried a wood 8x4 yet. I'm thinking a wood 8x3 would be a good ticket, but I don't know of anyone who still makes such a prop in wood.