I bet you did. I also bet that the stock airbox in aWRX is wayrestrictive compared to Audi's.

 

no the stock box flows really good on a wrx... it is said that an intake will make a wrx run too lean... but idk i got some good gains... it is said your safe with the stock airbox on a dub up to 400hp.

I personally think the sound of the intake, along with the possibility of HP increase is worth it.

 

I used to feel the same way. I had an 88 Prelude si with an intake and was ALLLLLLLLLL about it back in 97.....Then a 93 Integra with a cai, at the time I thought it sounded cool, and was too into the sound to admit to myself that there was a deffinate loss in low end tq. I had a 99 Integra GSR with cai, thought it sounded cool, and started to fess up to myself that there was a loss in low end tq, so i went back to stock box and was happy. A few cars inbetween, and then I got my Audi. The mod bug set in, and thewant for the sound and "possibility of added HP" came back to me. First I did the air box mod.... Sounded pretty cool, not as loud as an intake, but a definate loss in low end tq and probably negative hp gains. So I bought a used stock (non hacked) air box. Then, for fun, Ibought a cone filter and rigged up a good heat shield. Louder than the box mod, and even more loss of low end tq and also a noticeaable loss in mid range. Back to stock air box and I couldnt be happier, and I will never get an intake unless I have a giant turbo under the hood or a car with a restrictive air box. So thats at least 3 out of 4 cars that I noticed losses instead of gains with the use of an intake/cai. I kept trying all because of the sound I wanted. I finally realize that sound doesnt mean ****. If I hear a car WOTing/growling with a CAI coming down the road, all I can think to myself is "Im not impressed." (Unless its Arif in his 300whp whip.)
Just thought Id share my very personal experiences with intakes/cai's. No I never dyno'd to see if peak hp was increased by 1 or 2 hp anywhere in the powerband, but it wouldnt had mattered because I just couldnt deal with the low end tq loss which Id be seeing more often than a 2 hp increase at 7k rpms.

 

most modern intake/exhaust combos gain little if not lose power. Doing these mods on a older car still shows gains upto 15whp on intakes and 7-10whp on exhaust system (header included). You will see intake gains more on a N/A car than on a turbo car, exhaust on a turbo car are huge to minimum on a N/A car.