Originally Posted by Cryokid
I've worked with Cryogenics for the last 37 years and have really enjoyed reading this thread.
Let me start out with some basics on CO2 and its properties. It is stored in high pressure cylinders as both a gas and a liquid. Depending on the cylinder design, you can dispense either liquid or gas, but in this instance, they want to use the liquid. When the liquid is piped to the front of the intercooler and released to the atmosphere, it goes through a phase change and turns into both a cold gas and more importantly -109ºF dry ice snow. This would give you a much higher delta T in the intercooler and be much more effective than just a water mist, although this works to some degree.
Since CO2 puts fires out and is used extensively as a fire extinguisher, it would be good to keep the gas away from the intake. You wouldn't damage the engine, it just wouldn't run very well if at all.
Placing a block of dry ice on the intercooler to precool it before a run would accomplish the same thing, it just wouldn't be as easy to apply. Be very careful handling Dry Ice, remember is is extremely cold. As stated, CO2 is very inexpensive and should be available at most welding shops. In bulk form, it actually sells for as little as $50/ton to large users.
i actually considered geeting a bottle of CO2 and spraying the intercooler/engine bay (away from rubber hoses maybe from underneath) with it before runs