Might as well add an explaination about the Good the Bad and the Ugly in regards to Nitrous Oxide (N2O)
The Good:
Nitrous oxide is actually just a vehicle for Oxygen. All gasoline engines require two things to run. Gasoline and Oxygen. The more Oxygen you can get into your cylinder the more fuel that can follow it and the more power you will make.
Many ways have been invented to increase the amount of combustables you can get into an engine. Displacement, Forced Induction, Variable Lift etc… and Nitrous Oxide.
All of them accomplish the same goal. To increase the amount of oxygen available for combustion.
Nitrous Oxide is a very simple chemical compound made up of 2 Nitrogen Molecules and one Oxygen molecule. This is good because pure oxygen is unstable and reacts very easily making it VERY dangerous. Nitrous Oxide on the other hand is stable up to 300C, at 300C it splits into N2 and Oxygen, so unless your car is a giant inferno you don’t have to worry about exploding even if the tank is punctured.
That’s a neat thing about Nitrous, it only breaks down when you need it to, the compression stroke in the engine should be enough to heat the gas past 300C and thus when the spark actually fires the nitrous is now just nitrogen gas and oxygen.
Nitrous also has two other properties that give power BEYOND the fact it contains oxygen. The first is that as a compressed gas being uncompressed it cools the intake air making it denser. Denser air means more oxygen per volume which means more gas can be burned which means more power!
Some guys have Nitrous systems that don’t even enter the engine, it’s sprayed on the Intercooler to help cool the charged air.
The second related property is that Nitrous Oxide is naturally denser than air and contains more oxygen per volume than regular air at the same pressure.
The Bad:
Nitrous is treated as a quick boost. Unlike a turbo build up etc it’s VERY easy to install a nitrous kit and thus things are skipped that would normally go into a turbo motor. If you’re turbo charging a car and plan on a 100hp increase you’re PROBABLY going to change rods, lower compression, retard spark etc… With nitrous most people just ignore that since it would result in worse than stock performance when NOT on the queeze. A quick 100 additional HP is still 100 additional HP your engine was not designed for.
The Ugly:
Another aspect that is forgotten is fuel. An engine that’s leaning out is prone to detonation. Fuel starvation is one of the main ways that Nitrous destroys engines. If your air/fuel mixture is leaning out you generally start to get detonation. Detonation is where the gas explodes BEFORE it’s supposed to… if you’re piston is still coming up when the blast wave tries to push it down say good bye to piston rings, head gaskets, rods etc…
Basically what’s happening is the lack of fuel means the cylinder gets VERY hot during compression, hot enough that the existing mixture of gas with the elevated levels of oxygen ignites BEFORE the spark.
All combustibles have a flash over point where the mixture of fuel/oxygen is at the right level that combustion can happen at lower temperatures.
I’ve done work for Kellogg’s corp and one time I went to their mill in London and one of the towers windows were all boarded up, it turned out there was an explosion due to grain dust floating in the air. The mixture was JUST right and a slight spark blew it all up. A pile of flour on the other hand won’t burn, even with a propane torch. This is also how those HUGE “daisy-cutter” bombs work (go look it up on google, they are teh cool). And coal mine explosions… etc etc etc…
Not to say that Nitrous will always do that. If your engine is properly setup to handle the power AND you’ve got a properly setup fuel delivery system then you can quite happily run nitrous as much as you want with no more damage than a turbo would cause… (infact less since you no longer have to worry about turbines breaking down and getting sucked into the engine, or oil starvation/clogged lines etc…)
Some ways to ensure you won’t detonate is to lower your compression, retard the spark and of course increase octane.
(Higher Octane gasoline actually burns slower/harder to burn than lower octane gas, but that’s for another post)
I’ve probably left some stuff out, but hopefully someone now knows more then they did 5 min ago 