---

Surline's engine is basically the same powerhead as the original poster's, since in those days the Mercury 115 4-stroke was a Yamaha powerhead in Mercury dress. The factory furnished the Mercury Vengeance prop, which is Mercury's basic SS prop, but also a very good performer on the Dauntless 16.

So that would be an alternative, mid-price range prop, less expensive than the SpitfireX7, and at only $289.

http://jacosmarine.com/new-mercury-pr...ropellers/

I am not a fan of these "whale tail" add ons, but if one is used the engine must be mounted up in the middle (3rd) set of holes so that it doesn't drag in the water at planing speeds. Generally, the right choice in a prop will eliminate the need for such a fin completely.