I was lying in bed earlier trying to get some sleep, and had a thought. It of course kept me awake, so I had to go outside to look at the truck.

The WRX Sti has a selectable water misting system for the intercooler in order to increase power when racing and such. My understanding is that a diesel's EGT's are directly affected by the temperature of the intake air. I looked at the intercooler tonight (damn that thing is big), and although the clearances are tight, it seems that one could run some tubing in front of the core with many small holes (like a #60 bit) drilled to make a homebrew misting system. A small 12V water pump to provide the pressure...

Integrate an ice can with a water spray system, and I'll bet I could get 45 degree water spraying on the intercooler core. With enough volume, I'll bet that could reduce intake temps well over 50%, of course depending on the actual "before" temps. If they are well into the 150 to 200 degree range...no problem...

Any thoughts?

You would be better off injecting the water into the air stream. Like some of us are doing here. This way you will use less water and won't need a huge tank in your bed.

Not a crazy idea depending on what you are wanting to do with the truck. I run a setup with 4 nozzles on my cummins when i am pulling. I have read of some guys that tow a lot using it on step grades. I am wanting to get a pre intercooler reading and a post intercooler temp sensor put on the truck to actualy see how effecient it is. I am not the only pulling truck doing it. It can make a steamy mess on your window though.

Iuse a Snow performance water/meth system on my cummins, I have it right to the intake. It lowers temps about 150 degrees. I'm thinking about doing the DMAX next. You could use straight water for cooling you just have to get the right size nozzles and psi figured out.

If your looking to do it to the intercooler you can find the kits at Camping World. They sell them for cooling the radiator but it will work the same. Small plastic hose with nozzle end that are adjustable.

You could also use something that is common in the turbo import market, called the cryo2 system, it sprays liquid Co2 onto the intercooler if you really wanted to drop the intake temps by quite a bit. Its not a very heavy system and is fairly simple but you would need at least two of the systems to cover the larger intercooler if not more. I don't think this would be a very cost effective approach compared to the water sprayer but on the track I've noticed that the tech's really don't appreciate you dripping water on their track!!!