Actually if wired correctly the safety solenoid opens when the system is armed. Then the secondary solenoid does the pulses. Its only in case the secondary solenoid leaks, This is why i recommend one on any system. I have saw intakes split in half due to a back fire when N20 leaked into the intake. This is the reason after i make a pass i always turn the N20 off, And bleed the line. Its better to be safe with N20 than sorry with N20.
progressive is out of my price range and with the small hit I'm doing I won't be needing for a while. I won't be able to do much above 125hp until I get bigger solenoids, larger carb plate and probably a separate dedicated fuel pump. So for now I decided to go with the MSD switch which has an on and off. It uses the pills but with Bryant's method we'll just install our own adjustable knobs on there. I ordered on craigslist used for $45.
