The sullivan will make some impressive upper range power over a 99,01 but with giving up the low range. I have yet to see any comparative dyno results between the two on the same car for exact numbers though. Modular motors are dogs down low, especially when you run low compression. I have been thinking about running the sullivan lower and HPP upper on my car when I go turbo but I don't know if its worth it if the car will have no balls down low. The fr500 intake is a very nice piece, best of both worlds, but it is very expensive.