Installing a high flow intake system is a great upgrade but it usually means scraping the factory snorkel and sucking in hot engine air. To regain the benefits of colder, denser outside air I designed this cold air box. It's constructed out of 0.030" thick aluminum forming 5 sides of the enclosure with the hood forming the top. Sheet rubber around the top forms a gasket to seal the box. At this point there is no ram air effect. I used an 8" by 10" plate angled up at 45 degrees mounted in the front grill to deflect air up toward the opening of the cold air intake. Eventaully I will mount a ram air duct in the grill and use 3" dryer vent to force cold air into the box.

Using a two input digital thermometer, I observed about 15 degree F differential during cruise and 40-50 degree F differenital at full boost between the temps inside and outside the cold box. After a hard run the mass air flow sensor is usually cold while the rest of the engine is quite warm, indicating that the system is indeed working.

Shown below is a drawing to make the cold air box. I used aluminum rivets every 1.5" to make the joints. The box is made from 0.030" aluminum sheeting. A brake and shear would be nice for construction but I was successful with just tin snips and a vice.