This is the craziest crap i have heard in a long time. Now i cant tell you what you do or dont feel, but i can tell you your logic is absolutely retarded. This is a turbo car. The larger diameter tube with high flowing filter will feed the turbo faster, which reduces spool up time. The faster you get that air in the motor the better. The idea that too much air can slow this car down is insane. More air = more power ALWAYS. The invreased IATs seen from a SRI could cause it to slow you down, but it certainly isnt the increased airflow.
+1 With comment:
These are not NA engines and we are not concerned with changing intake manifold runner size or length or varying cylinder head port or chamber configuration here. We are not concerned with lift and duration changes on the cams, all of which can adversely affect low rpm drivability.
Bear in mind that in our turbo cars the initial column of intake air must pass through the MAF, then get routed through the compressor side of the turbo, compressed and heated up inthe process, then through the intercooler and cooled back down and then on to the intake manifold.
We're talking only about the volume of the initial column of air that is available to enter the very first stage of the pre-MAF intake side of the system. At any given rpm or throttle body position, the engine is only going to use as much of that column as it needs, up to the point where the column ceases to supply the oxygen demands of the engine. Period.
Even with the given example of a small NA lawnmower engine (I had a Tecumseh one cylinder engine carb apart this weekend. The float was stuck and I was installing a new needle and seat for the float valve) I cannot see how this suggested theory can possibly hold water. Whether I ran that little lawnmower engine during tuning with no air filter or with the filter attached (even a somewhat dirty one) there was no discernable difference in throttle response. There is a difference in power if the filter is restricting air flow.
Note that I am not changing the size of the carb's butterfly. I am not changing the diameter or length of the little "intake manifold" between that carb and the intake port on the cylinder head, I'm not altering spark or timing or valve lift or duration. No matter what I do short of reducing the air supply to the point that the engine ceases to run well at low rpm,
there was no perceptible change in throttle response coming off of idle or at midrange rpm.
I think the posters are honestly but mistakenly placing way to much emphasis on subjective factors -- what they hear or what they "feel" by the seat of their pants, rather than objective measurements.
This is also why "butt dyno" reports are so notoriously unreliable. They tend to equate changes in sound with changes in power or report a placebo effect -- I bought it, I spent my money, so it must be producing more power than before. Usually a simple stop watch test before or after installing mods (way cheaper than dyno runs), or a relatively inexpensive accelerometer, can tell whether the butt dyno "feel" is valid.
There are ways to objectively test the theory, but It would be senseless to try. You would have to accurately repeat exact throttle body position at part throttle and measure part throttle acceleration at the same throttle body position with the stock air box and with the SRI or CAI and keep all other factors, especially intake charge temperature the same, and then simultaneously measure the time for the vehicle to change from one exact speed to another exact speed at those various part throttle settings. Not worth it.
Give me more available cold air and trust the MAF metering to decide how much of that will actually end up getting into the engine at various states of throttle position and engine load.
