Wanting to upgrade 25hp to 35hp

[ahenderson50]

I am thinking about upgrading my 89' 25hp Evinrude (25TECEM) to a 35hp. I was told this could be done by replacing the carb and heads with those from a 35hp. Does anyone have any insight on this or maybe a link to a previous thread about this (such as what year model range parts will work)? Also if anyone may have the used parts for this modification that would be great! Thanks in advance!

 

[blimp]

Re: Wanting to upgrade 25hp to 35hp

you can replace the carb with a 30hp carb, or a pre 70s or early 80s 35hp, but they will get you the same increase. They re-rated those in '85, the 35hp became the 30hp. You can do it, it'll give you a little boost, maybe 2-3mph gain max. Look on ebay, the carbs come up from time to time.

 

[blimp]

Re: Wanting to upgrade 25hp to 35hp

You would also need the larger intake manifold from the 30hp, or you can make yours bigger.

 

[Pintail58]

Re: Wanting to upgrade 25hp to 35hp

carb and intake manifold