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Firstly, I have an AEM high flow filter that I would recommend to everyone. It's miles ahead of the K&N oiled filters of the 90s.

Second, if you remove the top portion of the filter box, first from the throttle body and then from the lower portion where the filter rests, then remove the air filter, you will see at the bottom of the box a tiny relief hole most likely for moisture and debris and possibly for a slight increase in velocity as the air enters the throttle body. All I did was open this relief hole up with a 30" bit extension and a 3/8" drill bit (need a drill bit that has the standard screwdriver bit mount built in e.g. the hex shank mount.)

Maybe it's a bias but I swear by this, the engine sounds better and exhaust is more aggressive. For someone with the factory air box, a high flow filter, and some kind of exhaust system the results would be even better. I'll owe it to the 3/8" hole contributing to some sort of sweet spot resonance of the exhaust note and engine harmonics. I wouldn't cut out a huge hold because the engine bay gets way too hot to allow a larger volume of air in, but for 60 seconds of your time maybe it's worth a try.
 

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What is your assessment of this mod after a long time driving the car? Would you do it again? How did it affect MPG, throttle response? What about sound?
 

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*The Electrician*
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@arathol

What's your opinion on this? Worth a shot?
 

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Well, poking a larger hole in the box will make more noise. Won't make any more power. The stock parts (box and filter) already flow more than the engine can draw so a 3/8" hole won't make any difference.:dunno:
 

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Results of experiments like this are best supported w/ pre & post dyno & MPG comparisons. Numbers will prove their worth.
 

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*The Electrician*
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Well, poking a larger hole in the box will make more noise. Won't make any more power. The stock parts (box and filter) already flow more than the engine can draw so a 3/8" hole won't make any difference.:dunno:
I dunno, I do like more noise, and if Im not losing anything its tempting.
 

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It makes sense that you wouldn't get any performance difference with that small a change, but I could see the sound being different. Could you post a video?

I am going to install an AEM filter tomorrow and I will try to make a before and after video, although I'm new to this.
 
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