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Get yourself an OTR. but you require MAFLESS tune. I ran car at track with factory airbox with k&n air filter and then tried an OTR and went 5mph quicker plus intake temps dropped which gave me better fuel economy around town. I wouldn"t go for anything else. Thats my opinion anyway.
Or just cut a second hole in the air box and add another piece of poly tube. A lot of guys swear buy it. Cheaper too.