Horsepower Difference?

[danbouck]

I noticed on a few merc outboards that the engine displacement is the same but there is a HP difference. Anyone know exactly what is used for the added HP. Is it ignition and fuel injectors?

[nancur373]

I know the diff. between Johnson 9.9 and 15 is the carb.

[irishfield]

Yep... always a mystery. Different cam lift/timing/fuel jets/carb size/injector size etc.

 

Consider The Verado... 225/250/275 and 300 HP are all the same displacement and RPM range. Haven't checked .. but I bet the new 350 is the same displacement as well.

[Lostchild]

The computer is the only difference in some hp ranges. Changes fuel, spark, timing, etc. settings. You can swap out the computer on a 50hp with one from a 60hp and your 50 becomes a 60. The only draw back is the computer is close to $1000!

[danbouck]

Too bad you can't get a programmer to change the computer.

[irishfield]

The Verado is progammable. I had the Merc guy sit on my boarding platform with his laptop and update mine.. change some settings.. etc. Not sure how much they can change.. but gonna ask next time I see him. Maybe I can get 25Hp for free.