small prop big boat

[krisnowicki]

I have posted on here about my prop changes over the last week. I recently repowered. With my old 350 and 21p prop I would plane on demand and could travel with a loaded boat no prop. On my 305 now I went from 260 hp to 228. 32 horse power loss. Well I got out with a 17p and it ran fine wot was about 4350 with just me and the wife. Put 5 people aboard and man It would get on plane then rev to 3300 lugging the engine big time. So I am no considering moving to a 15p . Will this even be enough. My boat weighs about 3200 with fuel and no load. Am I looking in the wrong place is there a problem with the drivetrain. I have a 1.5 gear outdrive. The engine timing and fuel is set perfect. She runs like a top. Just looking for advice Thanks

 

[steelespike]

Re: small prop big boat

Well a 15 would put you at about 4,750 and about 3,700.
I did a little research it seems to me your boat could do a little better.Boats were not exacxtly like yours but same hp and some outweighed your boat by 3 or 400 lbs. were turning speeds in the 40s and some more.These were new
boats maybe we can't expect the same from a used boat.
If we had your max speed at 4,350 and 3300 might give us a better idea of your setup.Maybe you can fiddle with the weight distribution and careful trim.
with less power its tough to force the boat past poor weight distribution.
You might want to check timing advance and compression.

 

[krisnowicki]

Re: small prop big boat

Well I guess whats really bothering me is the loss of 6 inches of pitch with 32 hp

 

[Bondo]

Re: small prop big boat

Well I guess whats really bothering me is the loss of 6 inches of pitch with 32 hp

Ayuh,......

You could get most of that back by Regearing to a 1.65:1 ratio........

 

[krisnowicki]

Re: small prop big boat

would it be worth it? And what harm would come from it? I am just worried about the 230 hp 35 mph wot. If I could get back to a 1.65 with a 19p it would put me back at 44-46 at wot