I'm thinking about putting an engine on an airframe that is using a 16x8 prop now but only has clearance for a 14 inch prop. Can I step the pitch up with a 14 incher and still have decent slow speed pull or should I go three blade? What sizes do you guys recommend?

Hi!
Of course you can, but it will not work that good!
Is it a 1.20-1.50 four-stroke?? In that case you can use a 14x10 or 14x11 (14x12 ) prop.

Would extending the landing gear be out of the question...?

It's a 26cc gasser. I could extend the landing gear and that would probaly be just as easy. It's a trainer anyway and looks are secondary.

Extending the gear might be the best option in the long run as three blade props can be quite weighty and are sometimes difficult to find.

Karol

Hey MR. Bigg. Glad to see that you finally got that SV-26 out of moth balls.

Sorry that I can't help you with a prop. I'm using the Mike Dooley recommended APC 18 x 8.
She's a turnin 7300 RPM.

Ed

I think extending the gear is the best option also.

Ed, how did you drill that APC prop for the 2 bolts? Is there enough meat in the hub area?

On a 26cc you don't really need any additional prop bolts other than the centre one.

Karol

Karol, on the SV-26, there is no center bolt, only a smooth unthreaded shaft. Not the best arrangement in the world, but it works. Just make good and sure that the two bolts don't bottom out. Ask me how I know.

mrbigg, theAPC 18 x 8 had plenty of material, but I can't say that a smaller diameter one would.

Keep us informed.

Ed

Thanks for that bit of info Ed. Based on that I certaintly don't think that the SV26 would be my first choice for a 26cc.

Karol