I have sprayed anything and everything, including gasoline engines & diesels. I've used turbo kits in a bunch of configurations...twin turbos to large single turbos. Every damn supercharger setup from Vortec A-trim to YS-trim, ProChargers, Paxtons, Powerdynes, I tried them all at one point or another. I've used nitrous systems from so many damn companies that have come and gone, and even made some kits myself with stuff I bought out of Grainger catalogs and pieces I had laying around. My hands down favorite for a drag racing power adder is N2O. Super cheap, easy to tune, reliable, repeatable, no belts to throw, no exaust routing nightmare and easy to maintain. For a daily driver, I've been a turbo fan since I had my first turbo Buick. It's hard to beat the on damand torque from a properly sized turbo combination on the street, and torque is what makes it enjoyable to drive. Now if someone out there wants to take a Mitsu 2.0, turbo it, spray it and even get close to running 7's in a car with a production head, production block, production trans and tons of factory parts and you want to dismiss it because "he's spraying", what in the hell would impress you? Ride in a solid mid 10 second nitrous car and the last thing on your mind will be, "Well it was fast, but you were spraying." Fast is fast, no matter how you get there.
