I agree. I was running the fujita CAI on my 07. I got rid of it and went back to stock. Retuned last week and gained 7.7 tq/12.4hp. The piping was to big causing mid rpm power loss. The only thing that I would change is the stock rubber intake hoses. A hose with no ripples.

 

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Cobb makes a nice one, its on my list of things to buy.

 

I'm several years removed from my mechanical engineering degree (I don't get much time to apply it in law school), so please bear with me as I speak in general terms. Consider it this way: the flow profile of the air that is exiting the filter and entering the intake tube is uneven. It can have portions of higher velocity - particularly in the middle (picture a cone that represents the velocity of the air). This higher velocity air does not represent the average velocity by any means. However, this high-velocity air is what is being read by the MAF, which is applying that value to the whole of the air being sucked in. So the ECU then thinks that there is more air traveling faster than it would be otherwise. This leads to a richer condition, as the engine adds more fuel to compensate for all the air that it thinks is coming in which actually isn't.

Now the stock airbox doesn't present this problem due to the design of the filter and its inherent effects on the flow profile (picture not a cone, but more of a flat wall representing the velocity of the air). Because it doesn't have this problem, the ECU ends up reading it correctly and doesn't make the same mistake that it can with other short ram intake filters. The CAI, because of the additional tubing, allows the flow profile to settle down and is subsequently read by the MAF/ECU correctly.

Now is it 10whp? I wouldn't guess so, but the data seems to suggest that it is. Also remember that the dyno data for short ram intakes are inherently skewed to show more horsepower - how often do you drive with your hood open and the filter sucking in all that fresh air? So I wouldn't assume 10whp, but I've seen stranger things happen for simpler reasons than this, so it's not entirely surprising.

Hopefully that answered your question.

 

^if all of this is true then wouldn't it be safe to say a proper tune could correct the issue?

 

I <3 my Pop Charger

 

One big problem of that article was their definition of a velocity stack. What they count as one presents a big problem with me. The stack should be on the end of the maf opening like the stillen/JWT cone. But they don't use that style to test their theory about a v-stack possibly being a varible affecting the SRI's results. They use the generic type cone with some bastardization of a v-stack on the very end of the cone filter. Not the same thing.