I don't think the 310 HP engine will be able to turn the ACME 1281 prop at the proper wide open throttle (WOT) RPMs. Unfortunately there isn't really anything you can do to get more speed out of your boat unless you spend a ton of cash. The only option that I know of would be to drop a new engine in it or put a supercharger on the current engine. I tried everything I could to get a few more mph out of my 2003 with the MCX short of dropping a new engine in it and gave up and bought a new 197 with the LY6.
Hey Andyg Maybe you can help? Have a 2003 MC 197 w/ 310 hp. Mostly barefoot boom babies. Don't want to give up the boat because of 12 person capacity and have a large family. Want more speed top end for footing. Running stock 13 x13 OJ prop. Do you think the Acme 1281 prop would help? Thanks Danny