ok well heres the deal, if you put C02 into your intake it will stall out the motor. now if you use like the Cry02 system that uses C02, but it doesnt put the actual C02 into the intake, rather it sprays it into a little bulb that sits inside the intake and the bulb cools the air down as it comes through the intake. so there is no direct C02 being sprayed in the intake. cold air makes the engine run a lot better, like when ur car runs better on cold mornings