Can someone point me to a good writeup or explain the process?

I plan on getting a fogger for my car shortly and I'd like to two stage it with a 100 shot, then a 200 shot for a total of 300. (Or something similar.

Can this be done with one kit, or is a ulti stage kit two separate systems? This will be my first foray into multi stage setups.

Why not just a 300 shot, are you traction limited ? Multi stage systems are difficult. It is not as easy as it may seem to just add 100 + 200 = 300. The N/F ratio is much tougher to moniter in a multistage system. If you insist on a multistage system I would contact Jeff Prock at Applied Nitrous Technology.

I will probably be traction limited. I'd like to hit a small shot right after launch and follow up with a big shot once it's rolling.

I was just looking for something a little different is all. I've seen a couple of cars with multi stage setups, but haven't been around them enough to know how they function or how difficult they are to setup and maintain. I may just stick with a straight shot.

You could also try using an NOS progressive controller. I have several friends with small tire cars that use these. It will let you select the initial amount and time until the full amount comes in.