Prop Help

[Brian MAhoney]

I've been trying out a few props on my sport 20, fitted with a Speedmaster 21 hydro strut with the following results.

x440 with this prop the boat runs very well, pulls away from launch very cleanly and is very stable. I am getting cosistent speed reading of 42 and 43 mph

1440 lauches with this prop are poor with lots of cavitation, the prop does normally hook up but it can take a while. Once the prop is hooked up the back of the boat seems to be a bit "hoppy". Top speed so far 36 mph.

1640 lauches with this prop are also poor with even more cavitation. If the prop does hook up then it seems to be way too much prop as the revs drop and the motor does not rev out. I have not taken a speed reading with this prop.

All speeds measured on a Garmin Etrex

Is it just the case that the boat prefers X props? Or should I be looking to adjust the set-up to suit the lifting props? Do I need to be thinking of modifying the 1440 or 1640? I'd really like to get the boat running in the high 40's so any suggestions would be welcome.

Brian Mahoney

 

[gil sonsino]

Hi Brian

You can also try the X442 and if your boat hoops up just flatten your strut to minimize lift I'm sure you will run in the high 40's.

Gill

 

[Brian Blazer]

Brian,

I never was able to get 14 series props to work on the boat. The design doesn't like lift. Try the X442 or an X450 cut down.

Brian

 

[Brian MAhoney]

Thanks guys.

Brian

 

[nitrotoys]

You might want to try a 440/3 blade as well, Pitched up some.

A 442 with tongue removed as well, Some boats like 2 blades for speed, some like 3 blades for handling.

ABC Makes a couple too, I beleive the H4 or H7? I am not 100% on these numbers, dont have the sheet in front of me, but im sure they would work well too.

Tom