Jesse IL
11-25-2002, 06:23 AM
I was just reading an article in SCC that helps justify some of my feelings regarding performance of a CAI on a moving car. SCC had put a new nose on their Project 300ZX and were saying that their track results were disapointing compared with their dyno performance. They were thinking that turbulence in the area of their air intakes caused by their new front end was confusing the MAFS at higher speeds (90-100) and causing a false reading and low power. They were saying that they could feel the difference. I've been thinking this could be a problem with CAI's on the Celica for some time. I dynoed an AEM and Injen CAI on my car with the same TRD exhaust and found that the Injen held only about a 1HP advantage, and that only above 7200 rpm. The AEM had significantly more area under the curve and should be a better intake. However, on the track, I have trapped out at a significantly higher speed (and have seen other high trap speeds) with the Injen compared with the AEM. If you look at the design of the two intakes, the AEM places the intake directly in the air stream inside the bumper opening, while the Injen bends upwards and places the filter above this point. I am thinking that the AEM is placing the filter/intake in a very turbulent location and is suffering from a power loss at higher speeds. Regardless of the actual effect of "ram air", I believe that a sealed airbox surrounding the filter and connecting to the bumper opening would make a noticeable performance difference in practice. The air would be slightly pressurized and would be still, eliminating the power loss from turbulence.