I just got a new GPS -depthfinder for Xmas. I had always used the speedometer in the dash for reference and it read about 72mph along with the rpm gauge. It seems like the dash unit is way off. GPS says about 64mph, 5500rpm at WOT. My set up: stock 200hp Johnson, 26" 3 blade raker, 10 inch slide master jack plate. Looks like about 2 inch below pad. I believe the GPS is correct. I have not had this boat long enough to play much, but i have been raising the last couple times to the lake. I have access to a 24" 3 blade raker. Just wanted to ask if anyone has experience with this set up and would be willing to make some suggestions.
oh, one more question, when towing, i noticed that the boat bounces a lot, It bounces with the gas tanks full or empty....air pressure in the tires are at speck...any ideas?

thanks for your help in advance,
tim