Jesel has the best one I have ever used. I didn't like the Comp one. The way the threads are made, and no provision for a lock nut to keep those 3 threads per inch moving as little LOL. The Jesel unit is a 3-4 peice unit that can range from a lawn-mower to a Hemi. It came free with a purchase of those Cheap rocker kits

[color:"red"]65 Hemi Belvedere coming soon [/color]
[color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]