Just to complicate things, the 10% figure is about right for the larger newer motors, they have spiral bevel gears in the lower units, but the smaller motors, even most of the newer ones have straight cut bevel gears. The spiral bevel gears have a lot less loss of power through them than the straight cut bevel gears, to make matters worse, the less torque put through either gear type the greater the power loss. The spiral bevel gears run hotter but the straight cut bevels lose more like 15%.
Proud Owner of 1956 Vagabond, 1950 Flyer, 1956 Rocket, Co-owner 1952 Flash, 10-1/2 less than VinTin
Locomotion wrote: It looks like we will have data from a 30 HP E Tec soon!
I know the new motors are rated at the prop and the older motors were rated at the powerhead, so my question is what would the hp at the prop be for an older 35 hp Johnson/Evinrude? Has anyone heard any numbers?
I have a friend with a 25HP Suzuki 4-stroke on a Vagabond. He gets 27, maybe 28 MPH when he trims it right. I get 29 MPH in my DR with the same motor, but I don't have power trim, so I think he's able to trim his better than me.
Considering you will be out of country at times, if I were you I'd get the Tohatsu 50 HP 2 stroke. Parts should be available more readily than the older motors in out of the way ports. Its heavy though.
Thanks Locomotion! I'm not ask u.k ng what's "right" for me, that's a difficult choice that I've got to make. I am seeking experiences with different HPs on these hulls as too performance and fun. I had an old Starcraft 15' that started with a 33 hp on it which was great but felt like driving a Accord or something. Nice but nothing special. Then I put a newer 40 hp on it which certainly put it into the sports car realm! That hull was rated to 50 hp.