Why same displacement on Johnny 90 and115?

[Docja]

These two motors have same bore,stroke displacement. Does the 115 really develop more hp? Opinions on pros and cons of either? How about same comparisons re rudes?

 

[JB]

Re: Why same displacement on Johnny 90 and115?

They differ for the same reasons that 350 Chevy engines vary from under 200hp to over 400hp with the same displacement.<br /><br />Both are very good engines and develop within 10% of the advertized hp. The same is true of any outboard "family" that share displacement but differ in HP.<br /><br />Good luck.

 

[Boatist]

Re: Why same displacement on Johnny 90 and115?

Docja<br />Not uncommon. 9.9 and 15 that way also. The 15 has a bigger carb with bigger jets and that eaquals more fuel, air and power. Some motor have a tuned exhaust to increase power.

 

[Docja]

Re: Why same displacement on Johnny 90 and115?

Thanks JB. The sales guy says the same about +/-10% for hp ratings. He says the 90 turned out to be +10% and thats why its so fast. Is there any way to know if the 115 is 10%low on average? I know I'm being obsessive,but this my first new boat and a lot of money and I want to spend well.