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Discussion Starter #1 (Edited)
Is the current smart airbox/airtube/air filter constricting airflow?

Just curious about what others have found with aftermarket air tubes. Most of the references I've read here on SCoA refer to the aftermarket air tubes as a way of improving access to the filter--finicky and difficult with the stock set up.

I've also heard the stock air tube setup referred to as a "resonator." Usually that means it's designed with chambers to balance airflow to cancel out sound waves--designed to quiet the engine rather than to provide the smoothest most efficient airflow. The engine--to me--seems plenty quiet and I'd rather modify the air tube for best torque and most efficiency rather than for quiet.

I'll admit I'm happy with the stock power and am not in any hurry to modify anything in the engine. But I am curious about the intent of the design and whether it's as efficient as it could be. In my experience, some autos are designed with restricted inefficient intake systems (usually for sound reduction, but other reasons too) and others are designed with good flow and open enough intake to handle any amount of air the engine can really use. Usually this has to be discovered by those who modify and test, but I haven't found the answer on SCoA yet. Apologies if I've missed it in my search of the forum.

Same question with the stock exhaust. By the way, my preference for modifying is usually to increase low and mid-range torque rather than max. hp which usually only is felt at high rpm anyway. Removing intake restriction almost always helps low end torque but freeing up exhaust can hurt low-mid torque if you lose too much back pressure. Just curious what others have found.
 

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I agree, it does seem that the biggest benefit of removing the resonator is easier access to the air filter. As for the factory intake being restrictive, I don't have any personal experience since my car has the factory intake, but I can't imagine that an aftermarket intake will yield much, if anything. The factory intake is so short as it is, and the airbox seems fairly large for the size of the engine, I can't imagine there are any substantial gains to be had.

Now, I do imagine that removing the resonator box from the intake probably yields a very noticeable difference in terms of the sound level. Even the factory intake has a lot of noise compared to the majority of cars on the road, but that's due, in large part, to the fact that the intake is located just a foot or two from the driver's ears. Removing the resonator box would, in theory, only amplify that.
 

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Is the airbox/airtube/intake restrictive?
NO 99% of the time...YUP

The biggest restriction to air flow is YOU... You restrict air flow about 99% of the time with the Loud Peddle...!!! Unless the moment you start your car, you put your foot flat on the floor (100%) and never lift it up until you turn the car off...hmmmmmmmmmmm Don't go chasing a Red Herring... If your looking for that 1% gain at the Drag Strip where you use 100% Loud Peddle with the Filter totally removed, by all means do so...
 
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