I have one old style lower and one new style lower on my 37 AT. The new style is on the port side and blows out bad getting on plane and has higher slip up until 60 mph. I can't believe that the added case length causes that much slip problems. It is the same with 5 different sets of props. Thoughts?

That is really strange, I would think it would be the opposite. The old case is very blunt and I would think that it would have higher slip at all speeds. I've been thinking about swapping my bravo cases for IMCO cases to get my slip numbers down without going to 5 blade props. I'm not sure that would really change anything for the better, based on your issue.

What do you mean by old style and new style???

The old style is pre 1991 era with no oiler hole and the drain plug on the outside of the bullet. That old???
There are some variations in the newer styles.

Issues with hull in front of port? Water pick ups on port side? Maybe you just have a really wavy lower.

Yes, that's the one. That drive is not the one in question. Actually I could not get on plane with majority of props until I put in a 1" spacer, much better now. It's more of an annoyance than anything now, but I'd like to remove the spacer next year. I might just switch the drives around and see how that affects things. It does this no matter what direction I spin the props.

Doesn't having a different style lower on it cause handling issues? I would think at speed, the boat would have a tendency to pull.

Boat goes straight as an arrow and no handling issues to speak of. Only issue I have with the boat is the terrible list to the starboard side whether sitting at the dock or on plane. I try to offset that with different amounts of fuel in the tanks. But, as I use fuel the ride quality really diminishes. This winter I am going to rearrange weight to make up for the absence of the generator and go from there.

My 32 leans a little starboard at rest and at slower speeds as well. Its a weight distribution thing. Mine has the 2 factory installed batteries under the seat on the starboard and water tank is on port side. I never have any water in it. I added a 3rd 29M battery on the port side and it helped. If I have me driving and two passengers on the port side, its dead level.

I doubt the drives have anything to do with it, but swapping them side to side would verify for sure.

I'm going to also move my 2 batteries from the STBD to port and add another D31T for my inverter and I'll also stow my portable generator along side my port engine. I currently need about 350 lbs on the port side to stabilize the boat. If I can get it below 2 people I'll be content.

Griff PM me your address, I found the sendors.