I’ve recently wasted a lot of time in a flame war (pun intended) on Yellow Bullet about heating nitrous oxide bottles with a propane torch. For the uninitiated, a cold nitrous bottle screws up your tune-up, because the pressure in the bottle is dependent entirely on its temperature, and a cold bottle will make the engine run rich when the system is activated. To bring the pressure up before a run, a lot of racers apply heat from a propane torch. It’s easy, effective, and probably the most dangerous thing you can do to a nitrous bottle short of drilling a hole in it or whaling on the valve with a hammer. The problem is that it’s very easy to accidentally exceed the temperature at which the aluminum bottle is permanently damaged, leading to eventual catastrophic failure of the sort seen in the photo above. It doesn’t happen immediately, and there’s no way to tell that you’ve pooched the bottle until it actually blows up.
I’ve been told that “everybody does it”, “I’ve done it and never had a problem”, “pro teams do it all the time”, and even that it’s just my “opinion” that using a propane torch is a bad idea. Since I have a feeling that this topic will come up again on YB, I figured it would be worth spending some time to spell out the facts. That way I can just link to this post and go on with my life, instead of typing it all over again.
Using a propane torch to heat a nitrous bottle is forbidden by every nitrous kit manufacturer
It’s forbidden by the NHRA and IHRA rulebooks, too
If you get caught doing it at most tracks, the best scenario is that you’ll get your torch confiscated, and the worst is that you’ll be told to leave and not come back
There is always a chance that torching a bottle will damage it, no matter how careful you are
There are other methods of heating a bottle, like a water bath or an approved thermostatically-controlled electric heater, that have no chance of damaging the bottle
When a bottle fails, the release of energy is enough to completely destroy a car, and can conceivably kill anyone nearby
The people at risk aren’t just the racers who torched the bottle, but also include bystanders, other drivers, and even shop personnel simply refilling a damaged bottle
These are not matters of opinion. These are facts. As for opinion, well, there’s a word that perfectly describes the kind of person who risks other people’s lives and well-being for no reason, other than being cheap, lazy, or stupid - that word is “asshole”.
