Really get creative and you have to hand it to them.

Was bored today, so I built a CO2 intercooler sprayer... - RX7Club.com

I was looking into other options to lower IAT's without getting a supercooler JUST yet. And of course I had been thinking of CryO2 and/or a N20 Sprayer for the stock H/E...google it and sure enough an RX7 cat beat me to it.

Synopsis of this link:

CryO2 CO2 intercooler evaporation kit = ~$450

Same parts at home depot (with ebay for the gas/fuel solenoid) = ~$80

Effect = Ice on intercooler, but care must be taken not to allow CO2 into your intake.

For this problem I'm considering having all of my "spray" be pointed directly DOWN rather than INTO the H/E. simply because at boost the air behind the h/e...which now has extra CO2 in it...might get sucked into the intake.

I'll let you all know how it goes. Weekend project hooray!