I have an 04, 27 PD on a 15x65, thats at the gunnels, aluminum valco. It was originally a jet sled boat built in the 70's. I picked it up and did alot of work to it, reinforce transom, extra skin on bottom, etc. Boat is a nice layout, but the 27PD I have on it won;t plane with 2 guys, dog and gear. With just me and some gear it will plane out and I can get about 22mph out of it at 3850rpm. With an additional 300lbs, it won;t come up on plane. I have tried trimming the motor full spectrum of movement, no joy.
I have small pods I welded on, they help but it still won;t come up.
Anyone have info on props and how they might help? I don;t think its a HP issue, as the motor doesn;t lug, it just cavitates at a certain point, then its all over. Any help or direction would be greatly appreciate.

Your right ots not a HP issue but its also not a prop issue either. Its a hull design issue. I don't know a whole lot about pro drives but one thing i do know is they are very picky about transom height and angle...also pods are are probably not noticeable when you by your self but probably doing more harm than good with load. They dont allow water to get to the prop correctly

Whats the angle at the transom that works best for PD's?

Short wide boat and a small block isn't helping either. PD is either a 15 or 16 dog transom angle, but it's more of a "boat not made for the motor" problem. Surface drives are picky about the hulls that perform well with them, and when you drop to a small block the mismatch is magnified that much more.