Originally Posted by US///M3
I've never said they did...having the intake manifold air to water intercooler on top of the engine in autocross (low speed,high rpm) i speculate it will demand some icing down as well.
You need to read up in A2W inter cooling. Doesn't matter where the inter cooler is, as that's just the exchange to cool the intake charge via the cooling medium. The cooling of the actual liquid takes place in a front mounted radiator. He circuit is separate from the engine coolant circuit.
Benefit is the intercooler can be placed anywhere and does not need direct exposure to airflow. The intake piping does not need to run through the lower front. Benefits there are obvious. Drawbacks: need separate radiator to chill cooling liquid, ppm and lines.
BTW GM's LS9 has an A2W intercooler mounted on the top of the engine just below the blower.