Prop pitch???

[Faztbullet]

The project boat launched today!!!! Anybody want to guess my prop pitch????I know it already....
Boat; 12' x 60'
Motors: 2 x 225 Merc 25"length
Cavitation plate: 1.9 ft off bottom of hull( that is feet!!!)
Weight: 56,000+ plus below
4 passengers,100 gallon fuel, 4' x12' roll off box, 1 Terex TC50 excavator, 2 gas welders
Props are Rubex
WOT: 8 mph

 

[jimmbo]

Something in the 6 - 7 inches range

 

[Texasmark]

No. How did you SWAG what you had on it initially/decided to use for the first guess?

Edit: The shallowest pitch you had on hand or could buy to fit the LU......you used test props....grin.

 

[Faztbullet]

Hint they are 15 diameter

 

[GA_Boater]

25's is my uneducated guess. You need the power to move her.

 

[QBhoy]

I’m lost haha. 8mph wot ?

 

[Faztbullet]

They are 15 x15...….

 

[dingbat]

They are 15 x15...….

Makes sense...same size I run in an Enertia

 

[Sea Rider]

Should worry that both motors are revving to their max wot rpm range when transporting all the mentioned goods to work properly and safely regardless of the speed obtained. Will need to throttle much less when lightly to medium loaded or both motor will over rev badly.

Happy Boating

 

[Faztbullet]

Throttles does not need reduced as barge never planes...turns 51-5400RPM at WOT no matter the load as just digging a hole in water. Owner said yesterdays load over about 100.000lbs as mud is heavy!!!!

 

[jimmbo]

Too bad there isn't a Gearcase that allowed the use of the very large Bravo 2 props

 

[Faztbullet]

Already in the works as these motors use the stub driveshafts. Adapter plate and coupler in design to try and use Bravo lower unit. Just trying to figure how to cap off the big oil hole and have a neutral and reverse

 

[beerman2]

Assuming your props are turning at around 2000 rpms your pitch would be around a 3. Hard to figure it correctly with out knowing the engine rpms and the gear ratio.