Sounds like they are only good for drag applications - cool a few L of water in parallel to a w2a heat exchanger such that it can absorb more heat load before being soaked and increasing IATs.  This way airon unit doesn't have to deal with the full engine heat load, just needs time to chill the water over a period when the engine is idle and performance would depend on the size of the chilled reservoir + w2a heat exchanger.  
 
Thinking it through such a system you need to be able to bypass the HE while the aircon is chilling the water, then disengage the aircon when doing a run to minimise losses.

Better off moving the Water to air resivour to a better spot, even inside the cabin away from the engine as far as possible. (Lines next to the body loom hole right to the cooler in the standard spot).

If you're going to spend that amount of money just move the cooler to the boot and have a massive water to air system.

Just switch to Methanol fuels :D