I attend about 20 tractor/truck pulls every summer and I have never seen a tank with lines going into the stacks, not saying I don't believe you I'm just saying I have never seen it.
The only tanks I have seen guys use is propane tanks for propane injection.
As far as the smoke goes, you have to dump more fuel into your motor. You are going to need a programmer to do this.
The old 12v cummins (mechanical fuel pump) is just a matter of turning up the fuel pump, but since I'm assuming you have a newer PSD, you will need a programmer bc yours is all electronic.

If you still can't figure out what the tank and lines are for, just ask the guy that is using them.