So you've finally done it--you listened to Gus, Paul, myself, and others... and you bought a turbo minivan. Congratulations! You've just taken your first step into a larger world of fun. Now you want to intercool your new baby. This makes sense--intercooling offers numerous benefits (Gary Donovan lists a number of them here). It's a good idea for any turbocharged engine.
So what exactly will you have to do? Here's an outlined overview of the steps involved:
Right off the bat you need to know exactly what you'll be stuffing into your van. My choice was guided by two criteria: I wanted the biggest cooler I could fit... but I was not going to sacrifice the A/C system. Since the condenser is out in the nose, this narrowed my choices considerably. The infamous Volvo cooler turned out to be the biggest which fit without interference, so I chose that one. If you're willing to sacrifice the A/C, however, there are far better choices out there.
This step is certainly straightforward. The grille and headlight bezels are held on by simple screws. The bumper is pretty simple to figure out how to remove but be aware of how the plastic bumper end caps are held on--don't destroy one! If you remove the hardware which attaches the caps before you remove all the bumber bolts you'll be fine.
Now is when you hold the intercooler up against your radiator and visualize exactly where and how it will mount. Once you know this, mark holes for the circular saw. Be paranoid and re-check and re-re-check your marks before actually carving up your van like a Thanksgiving day turkey!
Look at that picture and you'll notice a tranny cooler. My van had a smallish aftermarket trans cooler in place when I bought it. I realized that getting to the radiator would be tricky after the cooler was in place so I decided now was the time for an upgrade. I went shopping and bought the biggest trans cooler made which fit on my radiator! (Hey--your trans can never be too cool.) You may want to think about this same upgrade while you're at it.
Another possibile problem is the radiator itself; relocating it may be in order. I had to move it about 1 1/2" to the right (toward the condenser) for the turbo-to-cooler hose to fit. This was very simple; I just drilled some new holes for the speedinuts and then reattached the radiator to the van. The upper hose was trimmed about an inch to restore its natural curve; the bottom hose is situated such that I didn't have to trim it. YMMV.
Before you actually mount the cooler, it is a good idea to touch up any bare metal with some spray paint, primer, or what have you. Once that is done, mount away! I know I'm making this step sound extremely simple, but in my case it was. I thought I'd need to mount some fancy brackets at the bottom to hold the thing up but I did not--the inlet and outlet rest on the lower core support and hold themselves up perfectly. All I did was add a zip tie at the very top to angle the cooler inward to facilitate fitting the grille.
You will need to do some research ahead of time, especially where the hoses and exhaust pipe are concerned. In my experience 2.25" pipe is the perfect size to use. The only potential trick is adapting the inlet and outlet of your cooler to this size. For example, the Volvo cooler has inlets and outlets which are about 2.5" or so. I solved this by using two pieces of 2.25" exhaust pipe where I had one end on each piece flared out to 2.5". After that it was a simple matter of using short pieces of 2.5" radiator hose to clamp everything together.
As for the actual pluming to the turbo and throttle body, I used some straight pieces of 2.25" pipe, a modified stock turbo-to-throttle body hose, and three radiator hoses from AutoZone (hose numbers 304, 395, and 531). Two of these hoses were used with no modificatons; I trimmed one end off the third one. Hopefully you can use these pictures to visualize how it goes together:
Now the trick is to get the grille to fit over the cooler. I bought some washers and stacked them to make 1/2" spacers, then inserted these spacers behind the inner ends of the headlight buckets. Since the grille mounts to these buckets, this has the effect of pushing the grille outward by half an inch. After that I just observed where the grille would rub the cooler, then trimmed those areas off the back of the grille. After a few minutes of carving the grille fit perfectly.
Modified: 2-19-08.