He doesn't like air/water I/C because of the way they operate. They're great for short 1/4 blasts, and usually work just as well under normal driving as air-air I/C's....The thing about air-water I/C's is that you need a resevior(sp) of water, a pump, transfer lines, and way to cool the water(extra radiator).......All that equipment adds up to a good amount of extra weight and also the space requiements. On the upside there is no need for a FMIC. So the stealth aspect is pretty good.

With air-water I/C you can cool the intake charge to below ambient outside temps. If it's 100 degree's outside and you're running 50 degree water past the I/C you're gonna be able to cool the intake charge to below outside ambient temps.... which isn't possible with air-air. With air-air I/C the best you can do is cool you intake charge to how hot the air is outside. So if it's 100 degrees outside that's as low as your intake temp is gonna be.

Also a neat trick with air/water I/C's is adding ice into your resevior to get an ultra cool water supply... The plus being that you could get your intake temps down to near freezing. Good for power! Downside is that it won't stay that way for long, so it's good for the 1/4 mile track.

Now in a perfect world you'd be able to keep the water down to below ambient temperatures at all times. But in stand still traffic, high heat, or hard high RPM driving, the water in the system will begin to heat up. After a certian amount of time the water will heat soak, and then you're cycling nothing but hot water past the I/C.


Well......thats a few reasons at least....I may be wrong though