I like your thinking but it won't yield any significant gains. There are a few problems, if you essentially chamber the air filter by boxing it and add a scoop to force feed it, the motor will still only pull what it needs as far as air volume. In other words you can only fill the airbox with the volume of air that fits, any excess will simply blow by, kind of like a cup overflowing. Another issue is that this will only start to work at high speeds, at which point your trucks air resistance is countering any subtle effects of the ram air.
There has been some testing before on restriction of the stock airbox, the test results proved that there is only minor restriction at high RPM, to counter it you cut a 1.5-2" hole in the front part of the airbox. I am testing the K&N vs modified stock airbox for fuel efficiency purposes, still testing the K&N to collect data. Lizard King has a scoop under his bumper attached to the stock airbox which helped with highway MPG's, he's currently designing a new version. Keep an eye out for that.
Again I like your thinking, not trying to kill your idea but save your money and effort.
Ram Air doesn't come into play until speeds over 150 mph. For any application. True ram air benefits the most be being well in front of the vehicle, like sticking forward 14" inches or so.
I know this from reading extensive research with ram air on Z06's - on that forum we have a guy that measures the A/F ratio at speed and with ram air comes increased density so you will be able to measure the data with MAF and A/F. he got a slight increase over 150 but not worth spending coin on aftermarket intakes.
I also remember reading about this type of thing in 1996 when the Suzuki Ram Air Direct SRAD system came out for the GSXR motorcycles.
one benefit of these types of modification is reducing the IAT which will reduce any knock retard timing being pulled. That only works for trucks that are sitting in traffic, once you get moving the IAT drops back down. This would be a factor if you are sitting in the staging lane at a drag race and your IAT is climbing and you ECU is cutting timing.
I do think it's a neat idea though! I was not aware about the airbox mod Drunk is talking about but it makes sense there are a wide variety of vehicles that see gains.. the Suzuki DRZ 400 being one of them.
Headers will probably be the best mod.... eventually i want to drop an LS3 motor in my truck.
I thought I heard my name from over on that "other" forum. I must respectfully dissent from the majority opinion here. I have been running and testing Ram Air Intake Scoops on my truck, in various forms, for over 100,000 miles. I have gathered data, fined-tuned, made mistakes, learned from those mistakes, and made progress. Last summer I was turning 22-23 MPG on the highway at 70 MPH. Granted I have several modifications working in conjunction with each other and I seem to be most fortunate in that I have stumbled upon the correct combination of elements to put me where I am at now. Having said that my Ram Air Intake Scoop has garnered me the largest gains of any modification - driving habits constitute a large improvement as well.
I have found that the stock intake can benefit from a Ram Air Intake Scoop but there are limitations and caveats. The notion that the scoop can ingest water and hydro lock the motor has yet to hold (pardon the pun) water. I have never drawn any water up into the air box - ever. I have driven through deep puddles (not intentionally) and through six hours of relentless thunderstorms with no significant water in the air box. I have had moisture but no water in the sense that the air box becomes a bath tub.
Placement of the scoop is critical in terms of clean air and air pressure. Without air pressure the scoop is little more than tastless bling. It has to build pressure in order to work. Sealing the scoop, uptake tube, and air box is critical to building pressure. It is this pressure that enables the motor to breathe easier. There is a residual vacuum or pumping loss inherent in any conventional motor - equalizing this or pressurizing this helps.
I do all my work based on fuel economy and not the mainstream performance improvements. I cannot speak to performance improvements with a scoop but I can state that I see improvements in fuel economy at anything over 40 MPH as compared to pre-scoop numbers.
I am currently working on a new scoop in the bumper which is a location of higher air pressure and cleaner air than the previous location below the bumper. I am also testing some theories based on the Bernoulli principle and hope to have a new scoop/air box ready for testing in a few weeks.
My last set of calculations indicate that my scoop at 70 MPH generates less than a pound of pressure gain in a prefect system - mine is hardly close to perfect. Even so, the little boost that it creates is enough to offset pumping losses and help my fuel economy a little.
