No top end

[2FastLX]

My car was the same way. It would begin to lose all of its power at 4000rpm and would barely make it to 4500. After putting on my L/T's, Pro Chamber crossover, and cat-back it climbs hard all the way to 6000rpms and acts like it would go all the way to 7500rpm or so if it wasn't for the rev limiter.

If you can get your cat pipe removed easy enough (those bolts are a &!+$# to break lose sometimes) you can see if that is your problem. If you can't see light through the cats they're plugged. You can also take it for a spin with open headers and see how well it climbs without the cats =)