For a long time spraying lots of "dry" nitrous into an electronically fuel-injected engine involved complicated plumbing and fuel pressure issues, and swapping in some very big fuel injectors to add the proper amount of fuel at the proper time. Unfortunately, big injectors don't like driving at part throttle, and most cars equipped with them became temperamental on the street. NOS has changed all that with its new NOSzels EFI nitrous system. The NOSzels are a unique type of fogger nozzle that is installed between the fuel injector and the intake manifold bung. When the nitrous system is turned off, the engine's fuel injectors work just like normal. When the system is activated, the nitrous spray helps to further atomize the injector's fuel, adding more power to the engine than just the nitrous/fuel spray would alone. Since the NOSzels are a "wet" system and spray their own fuel, there's no longer a need to install huge injectors or increase your fuel pressure when you hit the button.
Back in the November '02 issue we showed you the buildup and dyno test of an engine affectionately known around the office as "The Coolest Rat." This Rat was deemed "coolest" because it had no trouble cranking out more than 615 hp and 580 lb-ft of torque, all below 6,000 rpm on pump gas, and it idled at 700 rpm! However, being the horsepower junkies that we are, all that was still not enough, and we thought a shot of NOS would be the next coolest bolt on. Luckily for us, the folks at Holley Performance Products-the makers of NOS-are just as addicted to horsepower as we are, and they had just what the our EFI'd Rat needed.
After installing and thoroughly testing the NOSzels, we are convinced that they're one of the coolest bolt-ons we've tried. The installation was simple-although it did take quite a long time because there are so many fittings to install-and tuning it was extremely easy. In fact, when comparing the NOSzels to normal-style fogger systems we've run in the past, things like jet changes are simpler with the new NOSzels, and working with the high-pressure plastic tubing was easier than working with steel lines (although some folks are not sold on the looks of the plastic lines; they like polished stainless). On a scale of 1-10 we would rate the NOSzels in the 9s. Not only did the system perform better than expected (it made as much as 50 more horsepower-350 hp at the 300hp setting-than NOS claimed it would), but it was so simple to use that we felt very confident when the time came to hit the button. Also, check out how amazingly close the extra power was to NOS's estimation. Example: the NOSzels added 103 average hp at the 100hp setting, 171 average hp at the 175hp setting, and 342 average hp at the 300hp setting!!! When NOS says you'll get an extra 100 or 200 hp with its kit, you can bet you're getting exactly that or more! While the total cost of the system is a bit on the high side for a nitrous kit (around $1,500 last time we checked Jeg's Web site for NOS PN 8008), there aren't too many people that might buy this kit who haven't already spent at least five times that on their engine. And for the money, there's still very little else on the market than can add this much bang for the buck. If you've built a serious EFI motor and are anxious to top it off with the newest in high-tech power adders, then the NOSzels could be the next best bolt on for you.