A buddy of mine bought his wife a Honda Odyssey with the 3.5 Vtec (SOHC). Getting ready for a long road trip to Alabama, he wanted to do something more for the intake than the K&N filter. I gotta describe this intake. It'* ridiculous:
There'* a tiny snorkel trying to draw air from directly behind the driver'* headlight. Except there are no gaps there, so it has to draw somewhat from the engine compartment. The snorkel goes DOWN into a HUGE resonator box, about the size of a half case of beer. 3 chambers in it that I could see. The box is located under the airbox/battery tray forward of the LF wheel. Air comes back up out of it into the bottom of the airbox, with a small diverter and heat exchanger with coolant running through it to pre-heat the air when cold. Odd setup, with a flapper to select resonator air, or pre-heated air.
We removed the resonator last night entirely, and ran a 4" duct from the bottom of the airbox to the LF opening for the foglights (his van doesn't have fogs). This opening is in the front lower airdam (one on each side) but the driver'* side is already open. We're installing a flange tonight so that it can ONLY draw air from the outside.
Should be good for a little snappier throttle, and at least 1mpg more in efficiency. We also removed the upper intake cosmetic cover/heat trap for the summer.
Odd ridiculous setup. Having a resonator chamber larger than a truck battery?