For all the time spent on this and the previous forum, I have yet to be convinced that you can do a simple impeller change and make much of a difference in performance...EXCEPTION: if you boat at higher elevations, then the balanced pitch impellers that your boat came stock with, won't have the hole shot as they would at lower elevations. And all boats suffer a horsepower loss as you get to higher altitudes...unless they are turbo or supercharged. This is due to a loss of atmospheric pressure. So if you do boat at a higher elevation lake, like over 3000 feet, then I might consider looking into them, otherwise, don't bother. Another thing to note...you can't have it both ways...a prop or impeller will either be pitched for power out of the hole or for speed. A power prop will produce more resistance and won't turn as fast at speed, so the boat won't run as fast as a boat with a "speed" prop. Conversely, a "speed prop won't get you out of the hole nearly as quick or as powerfully as a "power" prop. The stock impellers are a balance between the two. Any minor change in pitch to them will result in a loss in one category and a gain in the other. Just can't have both without balance. Now, you could have any nicks cleaned up, and that could improve your performance, depending on the need to redress them. Also, having them polished might give you an improvement, but will it be measurable? Maybe not on the speedo or gps...but your rpm's might change as well as your fuel usage. Efficiency is gained by many small improvements, not just one. As they say, it takes about $1K to gain 1 mph...if you want 5 mph, your spending $5K and so on.
