Elevation, out side temp, tire pressure, air temp, air humidity, wind (more so with our cars), windows up or down, a/c on or off, vehicle weight, acceleration, stops, idle time, city traffic, highway traffic, high way traffic heavy/slow, highway traffic minimal to none, all factor in to what your gas mileage is.
Intakes and our cars don't do any noticeable increase. Just because the pipe is bigger than our throttle body's, doesn't mean your magically getting more air in. If your intake follows the stock piping route you're actually loosing air velocity. The better the air velocity, the better you stand a chance at seeing higher gains. And the filter and pipe needs to be routed away from hot spots. And being as our plastic (absorbs heat) intake manifolds, tiny ass throttle bodies, and intake kits available, a K&N Drop in, and removing the intake resonator is probably the best bet.
For those running cold air intakes, you've got this problem. Heat soaking the filter. Blacktop gets crazy hot. And heat rises. So if your filters somewhat close to the bottom of your bumper, prepare for heat soak start ups, and idling at red lights/drive thru's will probably cause your car to run crappy for a few minutes or seconds. If you're intake is running in any hot spots you may have been better off just using a short ram.
I chose the route of going with a knock off intake from eBay. It is short ram, and runs straight to behind and between the headlight and battery. So I gained air velocity, BUT not any more than stock. Why? Because the throttle body, can only let so much in before its air velocity is maxed out.
Ok, so if you want to actual see gains with air intake modifications just a intake is not the route to go.
The best gains will be seen from a Turbo or Supercharger. Forcing air in, is going to show the most gains.
Too costly for you? Ok, so try this. Ported intake manifold (or a aluminum manifold with larger runners than OEM) and a ported throttle body. There you should actual notice gains in hp.
Want to stand out from the crowd, and still show gains, while being different? Independent Throttle Bodies. Now this would take some custom CNC machining to make a manifold plate, then some welding to make runners and mounts for the throttle bodies, some thinking on how to get all 4 to open at one time the same amount, and of course, money. But that will show good gains, and look stunning under the hood if finished product looks professional.
I don't think someone else's question about snow was answered either.
Is snow like water with a cold air?
Yes. Infact, when snow melts.... what does it turn into? That's right. A little high quality h2o. So lets say its really snowing like a mofo out there. And you have to drive threw a drift, or snowy parking lot, and you're air filter sits low. You risk a chance of getting snow on your filter. And as the car is sucking air in, your sucking the water threw the filter, and drinking it up. So snow is bad. Fun, but bad. I hate snow. Snow sucks. But I do like snow in empty parking lots
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