Don: I'm about done dialing in the performance on my rig (if you recall, 2007 Triton 215X w/ 250 ProXS). I have tried about 8 props and every engine height. Based on comparing notes with others with the same setup as me (on Walleye Central boards), others seem to consistently get 3 to 5 mph more on top end, and some of them have hardly done anything to dial in their rigs.

Anything that would cause top end to be approx 3 to 5 mph below where it should be on the '07 250 ProXS but would otherwise not significantly adversely affect overall performance? The motor seems fairly smooth and has decent holeshot and decent mid range and I have been propped between 5800 and 5900rpms. I get an average of 4.5 mpg per SmartCraft if that matters. The throttle plates do appear to be opening completely.

And to answer your question (before you ask it), I have been using Seafoam with every tank of gas. I have noticed fairly quick accumulations of soot on the INSIDE of new props I have tried (not on the outside). As a result, I have just switched to Quickleen.

I think I have about 60 hours on the motor (I wil have to check to be sure on this).

I do not have any good reliable Merc certified mechanics in my area, so if anything comes to mind to point me in the right direction I would appreciate it. Thanks!