'67 NOVA SS* 400 small-block bored 0.030 over to 406ci* Stock cast crank and rods, balanced* Speed-Pro forged pistons, 9.7:1 compression* Melling RV cam, stock rockers* World Products Sportsman II heads with 64cc chambers* Edelbrock Performer intake* Stock Quadrajet carb* GM HEI ignition* 2 1/2-inch Corvette exhaust manifolds* Edelbrock mechanical fuel pump* Rebuilt TH350 with stock converter* NOS Cheater nitrous system* Stock springs front and back* Lakewood 90/10 shocks* Homemade traction bars* Car weighs 3050 without driver* All tests run with 11.5-psi tire pressure* All times corrected
Blanket StatementsGranted, it's pretty cool to hit the button on NOS' new Pressure on Demand system, aka the P.O.D., and hear the remote opener crack open the bottle. More important, however, is the system's ability to automatically monitor and maintain a given bottle pressure. According to NOS, the system will hold the bottle's actual pressure within 1 percent of the target pressure, which is programmable. "A nitrous bottle is a filled unit," says Holley's Matt Held. "The level of nitrous drops as the bottle empties, but fuel pressure stays constant. This creates a mismatched N2O-to-fuel ratio. What we do is match the two up at a safe level-and the system does it automatically."
Our test subject's owner, Dave Stoker, noticed the difference during our testing. "Before, the car would stumble a bit as the nitrous level got lower," he observed. "Since we put the heater on, I haven't noticed it. The pressure level stays more consistent." So the benefits are twofold: A constant pressure level maintains a safe nitrous/fuel mixture, and also helps keep performance levels constant.