75 hrs 4strk or 90 hrs 2strk?

[Swaenemac]

My boat manuf recomends a 75 hrs. Per my research, I could put the 90 hrs (for more speed and power) since it is the same weight? Any help. Ok, let me be totally clear. I want to go faster. Has anyone ever done this? I am not worried about my warranty either.

 

[ezmobee]

Re: 75 hrs 4strk or 90 hrs 2strk?

Nope. A lot more goes into that rating than just weight. So you're limited at 75 no matter 2 or 4 stroke.

 

[5150abf]

Re: 75 hrs 4strk or 90 hrs 2strk?

I don't know that hey even consider the hang weight of the motor, it is the torque it puts on the transom when under way that sets the HP limit.

A 90 applies alot more torque than a 70, with a 90 the transom would fail at some point, probly at full throttle so now imagine the engine at full throttle not attached to anything, stick with the 90 or get a bigger boat.

 

[GeneH]

Re: 75 hrs 4strk or 90 hrs 2strk?

I think he meant stick with the 75, not the 90. If you have an accident or get stopped by water patrol and are over your rated Horsepower, you could be in big legal trouble. If you own a home, you could be living in a cardboard box after getting sued.

 

[JB]

Re: 75 hrs 4strk or 90 hrs 2strk?

Being a little bit overpowered is like being a little bit pregnant.

Stick with 75HP or less.

If you want to go faster, optimize your rigging, trim, balance and prop. That will have more benefits than an additional 15HP.