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?