help with set up 27 warlock
 

I'm new to oso I'm trying to find someone that knows about warlock boats. I bought the boat with no motor or drive I put a max works upper on it with a sc -2 lower and 28 4 blade bravo prop. the motor is a 511 bbc .I got it running last fall and only ran it 3 or 4 times . I'm getting ready to get it out for this year and need to get the bugs out. The problem I have is the boat is hard to get on plane and I have a lot of prop slip when I figure it it's around 22 % . When I get it up on plane running the motor don't seem to be struggling or under a heavy load . When I start trimming it out it starts loosing speed very quick. The boat feels light in the water when it gets to about 50 but it's not hard to drive or to me it's not but I'm use to driving a Allison 2002. added a 1 in spacer and it seemed to help a little. I think it is still to high and it needs more prop. What is the best height and prop to run? Any help would be appreciated

Does the drive have a cavitation plate ?

Drive shower plate that's all. One thing that's bothering me and no one can answer is the spacer looks like it can help trap air and cause cavitation.