I don't know how you drive to achieve this. I've had 3 1st gens, & a B2 & have never came close to this mileage. I had almost 19 on a 1200 mile trip to NYC & back a few times. My current X did 18.5 on a 295 mile trip. And that's a on a light 5 speed 2wd sport. The others were all auto 4x4 4 doors.
Mine will do that at 65mph, and it is a 4 door 4wd with 3.27 gears, but I have done quite a bit more than he has, I also failed to note that I am running full synthetic fluids, including 75w90 in both diffs. However, the information he is presenting is obviously incorrect or a result of miscalibration of his butt-dyno. Running a 1600 watt amp is going to hurt his fuel economy and power as much or more than his CAI is helping it. This is why one of my goals for mine was reducing the load on the electrical system.
Plus, if he drives like he says he does, that would negate any change anyhow. Driving "like your 80" is the only way you can really take advantage of the fuel economy gains you would get from them anyways. But, I guess, people who read this thread can feel free to choose on their own whether or not an air filter gives him 25% better fuel economy and enough power to be noticeable. Hint, 5hp is not really noticeable on this platform, I don't care how sensitive people claim they are, and that would be a 3% increase in power. But yeah, like I said, if he wants to claim insanely huge fuel economy and power gains, and anyone believes that, I've got some beachfront property out in Death Valley to sell.
It is really like JD said, the biggest choke point in these engines is the valves, then the LIM, then the MAF, so unless you are doing your work there, you aren't going to make many gains from intake/exhaust mods. I have spent enough on bolt-ons to know that the man is speaking the truth. My biggest single gain was the electric fan, exhaust and intake mods still barely make as much difference as that did. His Spectre intake is basically the same as my KKM intake, just cheaper parts. It removes the stock air box and is basically a MAF adapter and a big ol cone filter. I am actually going to create a new air box that will draw some of the air from around the exhaust manifold to get hotter air to my intake to increase fuel economy. For anyone who wants to argue that cold air is better for fuel economy than hot, hot air works better since it is less dense, when cruising you don't need as much power, therefore you need LESS fuel and air. Plus, with warmer air, you have to open your throttle further, which means less resistance to air flow. Trust me, I can expand on my explanation and give you the physics if you don't, or you could visit any of the hypermiler forums and see what they have to say.
