Does anyone have 3-blade prop suggestions for this engine? Only mods are 11 mm carb and modified muffler. The plan is to use this engine on an airboat.
Is 3-blade or 3-bladed the correct spelling? And the one thing I cannot find is how to measure RPMs. Any help on how that is done would great too. Thank You. I'm working on this and a 33 cc Poulan.
Thank You,
Ken

Well a two blade prop in the range of 14x8 through 17x6 would work. A three blade would be on inch down in size. For example a 16x8 two blade would be about the same as a 15x8 three blade. So something around that size ought to do the trick.

The Poulan 33cc engine would run with 17x8 to 18x8 size two blade props, So you would just go down a inch in size for a three blade.

Welcome to the forum. Most optical tachs have a switch for 3 blade props. Otherwise, multiply by .667? on the two blade setting. They are usually about $30 -$40 last time I looked.

Thank You Both. You have been I big help. Those tachs are nice!