Upgrading from a 50hp to 90hp early-2000 Honda.

[mitchbuck]

I have a 21ft SeaCat Center Console powercat with twin 2003 Honda 50hps and the starboard engine powerhead is blown. I have been looking around for a replacement early 2000 Honda 50hp but haven't found one for a reasonable price in good condition yet. Anyways, my boat is a bit underpowered with twin 50hps and I've noticed that Honda 90hps of that vintage are about the same price. So I'm toying with the idea of selling the good engine and parting the bad engine and installing Honda 90hp in their place. First question I have is would I be able to use the existing wiring harness, gauges, and throttle controls from the 50hp on the 90hp? Second question is many of the 90hps are 25in lower units but my boat has a 20in transom and it can't be raised. To convert from a 25in lower unit to a 20in lower unit is it as simple as buying the 20in lower unit (with driveshaft) and bolting it on? Thanks!

 

[johnnygjr]

#2 i believe so,but might be pricy

 

[jgmo]

Are your transoms rated for a 40hp jump? I believe you can do what you propose but almost doubling the hull stresses would also be a concern of mine.

Good luck.

 

[mitchbuck]

#2 i believe so,but might be pricy

What I am hoping is that I could essentially sell a good used 25in lower unit for what a used 20in lower unit costs.

Are your transoms rated for a 40hp jump? I believe you can do what you propose but almost doubling the hull stresses would also be a concern of mine.

Good luck.

Yes. Some guys have put over 100hp on each side. Honda 90s would give best combo of efficiency, weight distribution, and speed