KEEP AWAY from systems that DO NOT use a BOTTLE HEATER and KEEP AWAY from systems that spray into the airbox!!! Thats about the TWO DUMBEST things on the market today... INTAKE PORT INJECTION (or spraying) is about the EASIEST and drilling and tapping into the block is the BEST WAY of doing it,,,but,,,theres guys (who sell their own systems) that want to argue with me... In order for NITROUS to do its thing (accelerate combustion) you HAVE TO HAVE a certain enviornment for NITROUS to do it's thing!!! TOO MUCH (or not the right type) FUEL or too much (or too little) nitrous pressure and TEMPERATURE (also liquid or vaporized state) have MUCH to do with the proper operation of a nitrous system ... A NITROUS system that sprays NITROUS ONLY into the airbox is ABSOLUTELY FLIPPING STUPID!!!! I could buy a $20.00 gallon of a "household chemical" (that you could buy EVERYDAY at HOME DEPOT) and produce MORE HORSEPOWER that "STUPID'S" system that blows nitrous into the airbox!!!! You DON'T have to buy the nitrous system from "stupid" and MY WAY (the 20.00 a gallon way) would only cost you around TEN DOLLARS in PARTS!!!! NO FILLING nitrous bottles and NO CHANGING nitrous bottles.,,,,,,, just an EXTRA 20.00 everytime you fill the sled up!!! A PROPERLY DESIGNED nitrous system will work JUST FINE and you will NOT BE WASTING nitrous OR high octane fuel like the "other systems" will!!!!! Take my word,,,, I've BEEN THERE AND DONE THAT!!!!