What causes no bottom end power?

Ok I thought it was the prop that was the problem since i bought the boat this year, but after trying 4 different props all that run boats the same as mine I have concluded it must be the motor. When I launch the boat engine revs to 2500rpm and then slowly climbs up in rpm. Takes about 15 seconds to get to 4500rpm then it noses over on plane. It seems fine after that I think it should have a little more however but you know lol. I also noticed when I load it on the trailer that I cant bump the throttle to power up on it if needed. The motor just stalls when it gets on a load at low rpms.

91 Johnson 200GT
all new fuel lines, filters, bulb, Lync&Sync, and checked the idle timing.

What is your prop to pad heigth?

10" jackplate 3" below pad.

And just to remind me the hull?

91 stratos 201 pro xl. 91 Johnson 200gt

Not being a SA but when was the last time you took your rig to the truck scales for a weigh in?

lol hmm never ...Should I find one lol?

decarb helped mine....

Wouldn't hurt to know how much you got for weight.

im having same problem with 389 javelin and 89 gt 200 with a 25 renagade if you figure it out let me know ive already done the decarb and weight all is good ive even indexed the fly wheel and checked each cylinder under a load all seems good try hitting primer when you punch it that seems to help me i know that its a fuel issue just dont know where to start top end speed is good and so is idle