The air is drawn in from the front grill through the airbox, and then it goes to the turbo at the back of the engine. From there it appears to go up to the bottom of the fan housing at the front of the engine, and out of the top of the housing there is a hose that goes over to the throttle body. Assuming I have that correct, can someone explain the function of going though or around the fan housing, whatever is going on at the front of the engine? Thanks a bunch. Just trying to understand how it works.

intercooler.....decreases the temp of the air entering the engine (air gets pretty hot after coming out of a turbo.)

The intercooler is simply put an air to air radiator. Volvo has always ran massive IC's, usually some of if not the biggest in the industry. Back in the early days of 7 & 900 series B230FT engines the IC's were made of copper (heavier than aluminum but dissipates heat faster, also more $) and the spec on them was a 100 degree drop in temp between the inlet and outlet. If you had ever driven a non inter-cooled turbo you would wonder why anyone went to the expense and trouble of turbo charging a car anyhow.

Mark

Thanks guys for explaining a basic turbo concept (heard of intercoolers). My 280zx turbo had a terrible lag. Whatever Volvo did with theirs is far superior. I don't remember an intercooler on that car - maybe it didn't have one. When it got spinning it was great, but the other car was down the road by that time (:

You know being a Volvo tech you just get used to looking at the big ass intercoolers that they run. I was under the hood of a 280 or maybe a 300zx turbo and I saw what they were trying to pass off as an intercooler and it was a joke indeed. It was maybe 1/2" thicker but it was only about 1/4 the size overall and I really need to emphasize MAYBE 1/4". So you can now really appreciate the difference a real intercooler makes.

Mark