Ceezer said:
Why do you think CAIs are a joke? Alone, yeah, they aren't worth much but once you've added a set of headers and a good exhaust to open everything up you don't think they out-perform a stock box with replacement filter? I honestly don't know because I've never done a comparison on the two.
Ill just give some info, and you can draw your own conclusions, some of it I will explain in more detail so its understandable.
I'll begin with Air charge, and this is specifically what the argument for a cold air intake is. Cold air = dense air. hot air = less dense. Dense = more oxygen molecules per cubic feet. If you ever read any articles on heads, intakes, throttle bodies, or even carburators, they all talk about CFM, cubic feet per minute. The more cfm your heads/intake flow, the more power you can make. Its simple. HP comes from oxygen and fuel. increase both you get more fuel. Anyway cold air = dense air. remember that.
Stock replacement K&N or Airhog filter is drawing air through the inner fenders from outside the engine bay. Its drawing cold air from outside the engine bay.
A "COLD AIR" intake is generally made of shiney chrome piping so it looks all pretty, and a big conical air filter that is open inside your engine bay. What does this mean? Its drawing HOT AIR from your engine bay into your engine. Remember cold air = dense, and hot air = less dense. the more dense the air is, the more power.
Not to mention the chrome steel pipe that the air is traveling through, a GREAT conductor of heat I might add. Not only does this chrome pipe absorb heat from the engine bay, it naturally heats the air charge up even more that is traveling through it. Sure they claim results on a dyno of power gains, but for the most part those dyno tests are done with cool conditions, open hoods, big fans blowing to keep the temperature down. AFterall, how will they sell an intake if they advertise you will lose power.
Does it free up the intake flow? sure, and that obvously helps. any time air has to bend and curve instead of flow in a straight line it loses velocity. The stock air box with its plastic/polymer/eurethane construction, as well as the air tubes flowing to the throttle body, don't absorb anywhere near the amount of heat those chrome pipe cold air intakes do.
Even if you don't think the hot chrome pipe portion is a big deal, its still a conical filter sucking hot air from your engine bay, instead of cool air outside of the engine bay (stock airbox)
I was dumb enough to buy a CAI for my old 93 mustang GT that I had, and i burnt my hands very badly on the chrome pipe after driving around one day. It never clicked that putting a chrome pipe 8" above an exhaust header that is anywhere from 800-1200 degrees would be a bad idea until i touched the cold air tubing after cruising around.
This is just my opinion of course. Ive been a car mustang nut for the past 10 years so ive made enough mistakes with parts.
what exhaust are you guys running? Im getting 16.5 - 18 mpg in my tahoe currently, im just wondering if exhaust would push it over 20 mpg