12 ft v with 5.5 speed?

New to the forum, but been lurking for about a month now.
Got a question about the speed of my boat. It's a 12 ft v hull
not sure of the make but started out running a 2.5 Nissan and
averaged about 4 to 5 mph fully loaded which is my wife 7 year old
daughter,me, tackle boxes ,poles,2 coolers, trolling motor
and battery.Now I've got a 64 Johnson sea horse 5.5 that I just
Went trough and runs perfect but only getting about 5 to 6 mph
out of it and the only extra weight is the fuel tank which is a 3 gallon.
At this point I've tried a few things to gain speed like trimming engine
both ways but nothing changed, even by myself it really don't seam much
faster. Just seems like I should have gotten a little more speed out of it
considering the nissian 2.5 was about the same speed. The engine does have
a home made hydrofoil on it which I was going to remove and see if
That helps. Just curious if any one is running something similar and what
there speed is or if there is something I'm missing.
Posting using my phone so I apologize Thanks tw

Hey,

I have heard of some people getting worse results with a foil...try taking it off. You may find a slight increase but I can't see that motor pushing your boat faster than 6-7 mph...

Is it 2 stroke or 4?

Never mind I see it is from the 60's so it's a 2...

I have a 12' V with a '68 6hp and it isn't real fast. I couldn't give you an exact speed, but as my 150hp Ranger owning friend says "You will have plenty of time to enjoy the scenery while you get to where you are going."

I would take the foil off, it's not doing you any good. Try and move some of your weight around, move some more weight towards the bow. It might trim better and will gain some more speed.

I've got a 12' semi V with an old 3.9hp single cylinder merc on it. With nothing but me and 3 gal of gas in the boat, it tops out around 7mph. I've moved gas as far forward as the hose allows and I've moved forward until I can barely reach the tiller. Not enough improvement to be worth mentioning. With the same setup, I can take my brother and I, 5 gal gas, 4 poles, 2 big tackle boxes, 2 batteries and a trolling motor and still get 6mph. And if you add my brother and me together, we're 12' 6", and weight 470+. :mrgreen:

I've seen vids on youtube of guys running this same motor on 10-12' boats and it looks like they're almost planed out doing around 10-12mph. Only thing I can figure is they must be flat bottom boats and the driver weights 120 soaking wet.

Thanks for the reply guys, I'm the one that made and put the hydrofoil on the motor
it use to have one when it was on a geenoe and made a big difference but I think I will
just take it off and try it. As far as weight goes , I guess the best way to explain that would
be a pic if I could figure out how to do that on my phone.