In drag racing, durability is much less important than engine efficiency for a few, frantic seconds.
In such high-performance engines, an intercooler is often mounted between turbocharger and engine inlet. This boosts the efficiency of the engine and also lessens the tendency for knocking to occur.
Bless the Australians who seem to be experts in using a heat exchanger full of dry ice cubes to perform this function.
Today’s invention elaborates on this technique by using a block of solid nitrous oxide in an insulated box. This is dropped into place just before a drag race or timed run. According to my Boy’s Own Book of Physical Constants, this should remain a solid at atmospheric pressure whilst the temperature is kept below -90 degrees C.
Instead of having metal tubes running through the box (which add weight), my approach would be to freeze the nitrous oxide with a set of smoothly bent rods in place.
When these are withdrawn, a collection of smooth channels, corresponding to streamlines, remains, so that the engine inlet flow can be subject to minimal resistance.
As hot gas passes through the block it evaporates the solid nitrous -quickly widening the channels ( a bit like a solid rocket motor) and forcing combustion-promoting gas, plus cooled air, into the cylinders.