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Is there a significant difference in HP

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chris_v

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"I would like to increase my p

"I would like to increase my power. I currently have a 71 50hp and have an opportunity to acquire a 73 60hp for a reasonable price. Theses are both electric shift motors so the controls are interchangeable and a switch would be very simple. My concern is the power difference. I use the boat to pull my kids around on a tube and I fish out of it. Since the kids are small it does ok. Since the fish are small and few its alright, but I still would like more power. My concern is, is there a reasonable power increase to the 3 cylinder, or is it so slight I will hardly notice."
 
I won't quote expertly upo

I won't quote expertly upon the power difference BUT there obviously will be a somewhat increase of power between a 2 cylinder engine and a 3 cylinder engine.

HOWEVER.... Evinrude nor Johnson manufactured a 60hp engine in 1973. The 1973 model was a 65hp and it was not an electric shift model.

What is the model number of that 3 cylinder engine?
 
"Chris, I agree with Joe. The

"Chris, I agree with Joe. The torque "curve" on a 3 cylinder will give you a little better bottom end kick than a 2 cylinder. You may even notice it.

You probably won't notice much difference on the top end. An increase of maybe 3 mph under absolutely perfect conditions is all you would see with a 10 horse increase (in this horsepower range).

Unless you are certain that the "new" motor has been as well cared for as your current, it may not be worth the risk in going to another with an "unknown past" - these are after all 30 something year old motors.

My two cents..."
 
"I have looked at the 60 hp an

"I have looked at the 60 hp and found it is actually a 70 not 73. It is in fact a 60 hp long shaft motor and the condition of the wiring harness is questionable. I started it and looked it over and found it to be acceptable in my opinion with some flaws but definitely a possible candidate for a swap. This just brings me back to the original question is it worth the switch? It is electric so all I have to change is the motor, no controls. Super easy. Is the torque gain worth the switch or would a larger motor be advisable?"
 
"Chris, I deal mostly with sma

"Chris, I deal mostly with smaller motors - under 25's. Guys are always looking to change a 9.9 into a 15. My advice to them is always the same - "not worth it" - if you want a "noticiable" increase, move up to a 20 or a 25.

Likewise, you are comparing a 50 to a 60. The difference is fairly minor. If your boat is rated for say a 90, moving up to that would make a difference you would notice.

I'm certain that simply going from a 50 to a 60 (even with the extra cylinder) would produce such a minimal performance increase that you would have to lie to yourself in order to really justify the swap - a little better, but not significant.

But it really comes down to what you are trying to achieve.....

If your current motor is "tired" and you were going to replace it anyhow, and this 60 came along - sure, wise move - but if you are dis-satisfied with your current performance, forget the 60 and invest in the maximum horsepower you can hang on the back of your boat...."
 
"Thanks for your expert opinio

"Thanks for your expert opinion. My motor is not tired, just a little small, yet sufficient in the long run. Thanks again.
P.S. This will actually be easier than the simple swap. No greasy hands or back aches. Not bad!"
 
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