Are you trimming to far up causing blowout?

Check fuel pickup tube. Often time junk gets in there and limits the amount of fuel getting to the motor.

I had that issue and now the boat runs what it should.

No, definitely not trimming up to far.all fuel lines are new. Has correct fuel pressure at fuel rail

Are you hitting the rev limiter??
What drive are you running. That year boat could very well saturated with moisture. Have you weighed the boat and trailer?
What is the running surface like. Is it a painted bottom, is the bottom dirty are there barnacles on the bottom or drive. Need more info
formula's have a natural hook in there hulls about a foot forward take a 6ft straight edge along the bottom and see how straight it is.