CAI indepth.....

[Longshot270]

Originally Posted by ticopowell

It was the same diameter right next to the MAF, but it did remove other restrictions like in the fender, and it was a smoother path between the filter and the throttle body. Here is a good example of what I am saying about the CAI's I have dealt with. both were exactly this same idea.
the only think that I can think of that would affect airflow is that the air maybe be relatively faster or slower in that part of the tube versus what the stock tube would read. since this can affect that area without the MAF reading it (because like someone said the MAF covers only about 14% of the circle of air in question), that is why any adjustments would need to be made.

Well if the inside diameter of the housing is the exact same as the stock housing then you should be fine. The pipe after it doesn't matter and the open filter before it only affects performance through air temps. The issue is not that the MAF only covers 14% of the cross section, the issue is the air speed through the cross section. You are not measuring the actual mass of air, you are measuring a part of the cross section to determine the rate at which air enters. From there you can calculate the overall rate and then the mass of air passing through. You dont measure flow rates of a river by channelling it into a big cup. You find an area that has uniform flow, measure the rate there and the rate at which water is moving through the area. Increasing pipe diameter with the same air consumption rates causes the airspeed to lower and tell the computer to fuel less.

We are dealing with vacuum rather than pressure so the concepts are much simpler.