Question on minimum power for my 75' 20 SF

[Texascoastalfish]

Hey yall,
Survived IKE OK down here in Galveston County, I had bought a 1975 20' SF with an Old 1976 200 HP Johnson. It has seen ALOT of saltwater use and while I had a mechanic doing some work on it he broke off 5 bolts taking off heads to replace gasket.Its going to take more money to fix this as well as a bunch of brittle wiring. INSTEAD I want to put my Brothers 1979 90 Hp Johnson which was on our little tri hull which was crushed from IKE, but motor was unscathed. ( Until I can find a 140 looper or newer 150 saltwater series.) I have removed controls and motor and it sitting in my garage...My big question is WHAT can I expect from this V-4 on my SF ?( it runs really strong and had been rebuilt 1 year ago) I dont need 40+ mph, but I want to plane out and cruise at least 30 mph. Any one heard of this small of HP on a potter config ? I believe controls should hook up no problem
Any advice is greatly appreciated. !!

Any one interested in a 1976 200 with a few broke bolts ?

"Navy" Dave Elias
Galveston County, Tx

[Fr. Frank]

I own a 20' Seafari with a 90 Mercury. Cruise at 24-25, Top speed about 33-34.

I used to sell SeaCraft boats new in the early 80's, and I rigged more 20' center consoles with 85hp and 115hp Johnsons that any other size motor. In fact, we rigged more 85's than 115's. My current boat had a 120 Chrysler on it when I got it.

So, yeah, a 90 will work fine. Just don't expect to outrun any fast moving squalls.

[Bushwacker]

You'll obviously lose some speed but you may be pleasantly surprised to find that it'll ride better and the scuppers will work better because it's better balanced, in addition to using less fuel! I ran my boat for 31 years with a 1975 115, which was really about 90-100 hp at the prop. Ran it in some pretty rough stuff and it rode great! Remember that Moesly designed the 19 & 20' hulls in the mid 60's when the biggest motors weighed about 300 lbs! They weren't designed for that big V-6! Let us know how it rides with that lighter motor!

[small45]

my 18' sf with a 1989 omc 120 cruises at 24/25 mph getting approx. 2mpg top end is 34mph with two adults and full of fuel