I think if you do this, you should make sure that you have a foam seal between the top of the airbox and the hood.
The reason is that otherwise you are going to be drawing the hottest underhood air that comes up from the engine and sits right under the hood (hot air rises). You don't want to pull that air in, but rather the air from lower down near the front of the hood, which is why the stock airbox cover pulls from its lower front. Cold air is denser and thus makes more power.
I noticed when studying the K&N air intake systems, that regardless of which model truck they were designed for, they ALWAYS try to shield the air intake from that hot right-under-the-hood air (check it out on their website - they include a metal shield with a foam lip that seals to the underside of the hood when th hood is closed)
The Vararam designer has pointed out to me that the stock airbox has a significant design flaw: although the rectangular filter provided is fairly large, the design only actually pulls air from about a 5 inch diameter portion of the filter, due to the duct shape behind it. IF he is right, then the best strategy MIGHT be to:
- Provide ONE large opening (as large as the stock airbox cover will accommodate), centered relative to the ducting behind the airbox
- Use a foam seal on the top surface of the airbox to at least minimize the HOT air draw from above
- Do not try to "enclose" around the new hole, as its unlikely that the engine can draw enough air to satisfy it from just a 5 to 6 inch diameter opening.
Jim G
The reason is that otherwise you are going to be drawing the hottest underhood air that comes up from the engine and sits right under the hood (hot air rises). You don't want to pull that air in, but rather the air from lower down near the front of the hood, which is why the stock airbox cover pulls from its lower front. Cold air is denser and thus makes more power.
I noticed when studying the K&N air intake systems, that regardless of which model truck they were designed for, they ALWAYS try to shield the air intake from that hot right-under-the-hood air (check it out on their website - they include a metal shield with a foam lip that seals to the underside of the hood when th hood is closed)
The Vararam designer has pointed out to me that the stock airbox has a significant design flaw: although the rectangular filter provided is fairly large, the design only actually pulls air from about a 5 inch diameter portion of the filter, due to the duct shape behind it. IF he is right, then the best strategy MIGHT be to:
- Provide ONE large opening (as large as the stock airbox cover will accommodate), centered relative to the ducting behind the airbox
- Use a foam seal on the top surface of the airbox to at least minimize the HOT air draw from above
- Do not try to "enclose" around the new hole, as its unlikely that the engine can draw enough air to satisfy it from just a 5 to 6 inch diameter opening.
Jim G