Intake / Headers / Exhaust upgrade.

[mbeige]

Morrissey, if you like it to look stock while have the performance gains of the K&N filter, go for it

Personally that's what I'd do, but considering my car isn't tuned to extract as much power as I can get out of it, stock air filters do. Like I said just be careful of the MAF sensor especially on the newer cars. I think the advantages of using the old airbox is to get as much air volume as possible, and make sure the filtration area of the air filters are more than or equal to the ones they're replacing. I think that's the rule of thumb but I only heard that very few times so I'm not sure if that rings true to all or most cars. I'm sure the stock airbox will suffice but I'm worried about the small diameter of the stock tubing that might possibly restrict airflow, in your case at least.

I posted a thread a long time ago about the benefits of using K&N compared to other filters. I don't recall what thread I posted it in but I think it has to do with diesel engine aspiration.