What is the engine rpm at full throttle, aka wot? That's how you select a
prop. A higher pitch may prevent the engine from reaching the correct rpm
range at full throttle. The service manual will have the correct wot rpm
but I'd guess it should be in the 4200-4600 rpm range. If rpm is low at wot
then you need a lower pitch. If rpm is high at wot then you need a higher
pitch.

Trim tabs always help with getting on plan and allow a lower crusing speed
on plane. The minimum speed that the boat planes at is more a function of
the hull that it is the engine and prop. Though some props will provide a
little more lift.

That is a heavy 28ft boat to have a single 350 engine. Some would probably
consider it under powered. How old is the engine?

wrote in message
oups.com...

I'm looking for first hand experience if possible before buying
various props to find the best match for my 1988 Wellcraft Antigue
265.

I've used prop calculators and everything recommended for this boat
comes up as 14.5x15 to 23.

Currently I have a 14.5x17 on her. Top speed is about 30 in calm seas
and cruising speed is 26.

She seems to take a while to get on plane, but I'm used to a 20 foot
boat, this is a recent move to a 28 foot boat for me. Based on what
the previous owner told me, if there are 3 to 4 people on the boat he
would sometimes have to have them in the cabin to get on plane.

I'm wondering if I can use the trim tabs to assist in getting on
plane? I'm also wondering if I should increase the pitch?

My reasoning for that is with the 17 pitch top speed isn't to much
higher than cruising speed. So I wonder if it's possible the
additional weight reduces the speed from getting on plane.

The motor is a 5.7 with 260HP and it doesn't bog down at all when
throttling up. I'd also imagine with a higher pitch the engine could
be backed down to stay on plane and increase fuel efficiency.

Thoughts?