I'm no expert-but I did stay at a Holiday Inn last night

! I'll do my best to clarify my babblings previously... .
An EZ is a minor fueling box-it plugs into the Cummins ECM data link and manipulates fueling commands through that. Due to constraints there is only so much power it can achieve this way. It also plugs in between the MAP sensor to mask overboost signals being sent to the ECM that would cause defueling.
A COMP is a major fueling box-it also plugs into the ECM and MAP sensor and does the same as the EZ. To get the bigger power increases, you actually make a connection to a wire leading to the pump solenoid itself. The COMP forces the solenoid to stay closed longer through this wire thereby generating bigger power increases. You can run the COMP without hooking up this wire-you are then limited to the power increases available through the data link connection-around 60 hp at peak IIRC.
The Pulse is set up the same way as the COMP-if you want a moderate power boost you plug in the data link connection and MAP connectors similar to the above boxes. With the Pulse though-unlike the EZ-you have the option of piercing the pump wire to get a larger horsepower boost at some time down the road. Again not mandatory-just gives you more options at some point in time.
Piercing the pump wire is a definite warranty-voider... . so some avoid it. There are various stealth ways of piercing which by now DC knows all about so I won't go there-rest assured they've figured it all out and informed the dealer network accordingly.....
As for smoke control-the EZ has a 3 position jumper inside controlling its aggressiveness-or tendency to produce smoke off the bottom before boost catches up. IIRC the settings are 3 psi before fueling, 10 psi before fueling and 20 psi before fueling. The Pulse has 4 separate positions for aggressiveness-sorry I don't know the exact #'s. The Pulse also has 4 power levels that are selectable via jumper-the EZ is fixed to 1 only. Both these boxes are under-hood mounted... . not a big deal to change the settings-about a 5 minute job. The COMP mounts in the cab-it has 5 power level selectable on the fly via a front-mounted panel. Each level has 5 settings for aggressiveness that are also adjustable in-cab... . although it takes a little longer to set them-not something you'd want to do while driving and realistically something you shouldn't have to. I keep my COMP set on 1x1 for work time driving etc..... when I go to town I bump to 2x2 or 3x3 to make the truck way more responsive for lane changes etc.
Hopefully I covered all the high points etc. -you can find more info on Edge's website (
www.edgeproductsinc.com ) or I'm sure anyone retailing them can help you out more. My personal fave is Rod from Wildcat Diesel (
www.wildcatdiesel.com )-but there are lots of great guys to pick and choose from-in fact too many for me to name here.
Jason