85 -> 90hp? Possible? Whats different??? Also what parts for tune up

[87baylinercapri]

Greetings,


I have a 1987 85hp, but would like to bump it to 90hp. I have good compression on all three cylinders (120 on all three) and would like to know whats the made the 5 hp difference from 85 to 90???? Was it just a different set of carbs????? If so where can i get three carbs that normally go on a 90 that will fit directly on my 85?


On a side note, whats a good tune up to do on my 85?

I just added this year new fuel line, new spark plugs...but what else? Should i check the fuel pump ? I would like to make this thing run top notch!!

 

[87baylinercapri]

Re: 85 -> 90hp? Possible? Whats different??? Also what parts for tune up

no one???

 

[roscoe]

Re: 85 -> 90hp? Possible? Whats different??? Also what parts for tune up

Other than the entire ignition system being different, I don't know which parts make the extra 5 hp, or if there even is an extra 5 hp.

NMMA allows for 10% hp deviation to allow for manufacturing variances.
So who knows if the 5 hp ever actually existed.

But, the carbs, ignition, reeds, timing, are all different. Probably the pistons and the porting as well.

The 87 85 hp used an exhaust snout, and the 90hp used a dual or thru hub exhaust, depending on the year.

If you need the 5 extra hp, you would be better off putting your money and efforts into an Evinrude or Johnson. You will probably actually get the hp you need, and a better engine as well.