Yeah I will probably do it after this weekend.
As for the weight part...Yes I have gained about 15 lbs since I got the boat...LOL
There's your problem. j/k. If you went from 49 to 40mph, then 15lbs weight gain is not the problem. GPS isn't always accurate but only 1-3 give or take. Regardless, I recommend changing the plugs, oil and lubes and try running her tournament loaded. Once with your 19 pitch and once with a 20 pitch. You should see a big difference in holeshot and top speed. Give us an update once you've done this.
When I first bought my 165 Navigator. I took it out, it did 36-37mph. Then I started loading her up with life jackets, an anchors, fishing rods, tackle boxes, rain coats, net, push pole and extra battery and I was only getting 33-34mph.