Hello, MY buddy's got an 03 raptor 660 that dose'nt seem to have a good top end. All that is done to it is a proflow kit with a K&N filter. The low end is great on it but it dose'nt have the top end we think it should. My predator walks all over it. We tried lowerin the needles all the way down and it helped some but we think it should have more. Any help or suggestions would be great.