High Thrust vs High Speed Prop on 10 foot Deep V Hull

[ravencraft]

Hello I need some prop advice for my 6HP 4stroke 2009 Tohatsu please.

Boat is a 10 foot deep V fiberglass fishing boat weighing in at about a 160Lbs

The current prop is the 7.9inch 8 pitch comes standard
There is a 7.9inch 6 pitch prop available and a 8.15inch 6pitch elephant ear High Thrust prop available (seems to be the choice for the sailboat minded)

It will eventually get me onto a plane and move the boat quite well, but with extra weight in the boat the motor doesnt seem able to spin up high enough RPMs to develop the full 6HP. I realize going from an 8pitch to a 6pitch will affect my top end speed but i think the added thrust, reduced prop slippage will increase the RPM and get the boat moving out of the hole alot better.

My question......Should i keep the same high speed style of prop and switch to the 6 pitch?

Or should I use the larger diameter "elephant ear" style prop? The sailboaters all seem to switch to this elephant style as they are using small engines to push a heavy load, but can these elephant ears be run at wide open throttle on a small planing boat?

Thanks for the help

ps I realize a 9.9 would solve all my issues, but i really like the 30 lbs less weight and the fact that this little one lunger i am beginning to think runs on air.

 

[glengold]

Re: High Thrust vs High Speed Prop on 10 foot Deep V Hull

I have two props for my boat, one for heavy loads/watersports and one for top end. Get the lower pitch for heavy loads and make sure she doesn't over rev WOT.

 

[steelespike]

Re: High Thrust vs High Speed Prop on 10 foot Deep V Hull

A 10ft DeepV have you got a picture. A real deep V has something like 18 or 20 degrees or more at the transom.
Any way I think your better off with the highspeed prop.
The elephant ears gives better control for larger more difficult to control hulls that aren't going to plane.The 6" would surely help you plane but be aware it is likely to over rev with a light load.
You should get a tach to check your rpm before and after.There are a couple of tachs on the market Tinytach is one.