I have a 1996 wellcraft thunder 38. The claimed weight of the boat is 10,200 lbs...but, I have added blowers, transmissions, and speedmaster 4 drives, so I am sure she is a bit heavier than she was with standard equipment. I am trying to figure out where to go next on props. I set the prop shaft at 1.5 inches below the hull when I hung them. It is currently running a 28P, 17.5 diameter 4 blade clever.

I have tried everything under the sun for good planing, currently best i have found is a gentle roll in to 4500 rpm tabs down and it still takes a good while.(tried every configuration and trick i know or have heard.)

Yesterday with 3 people and about 100 gallons of fuel

3500 rpm was 49 on GPS
4500 rpm was 70 on GPS

Is that enough enougfor anyone to make an educated guess on where to go from there? The extended plane time sucks, but I'll deal with a crappy plane for a good cruise number and high top end.

Any thoughts?

Either you have to move drives lower or make an extended cav plate to help with the plaining problem . If you have any other questions feel free to call Dan MacNamara owner Team Archer Marine 949-646-9778