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  • Sept. 18, 2008 9:23 p.m. SVreX UltraDork

    I'm building a custom airbox, so I can use anything I want, but I'm curious for your opinions.

    If you could choose either, which would you prefer?

    I'm trying to save some bucks, but I gotta have good airflow.

    I'm torn between 2 perspectives.

    The cone has more surface area, but by nature of it's shape it demands convoluted air flow. I can build a box that would house one, but the cone design will basically mean the air gets stuck in a box then finds it's way through the filter without flowing nicely.

    The flat filter has smaller surface area, but allows very smooth airflow.

    Any thoughts?

    The car is turbocharged, so it may not matter significantly (I guess the turbo will suck through pretty much any weird configuration). Maybe volume is all that matters.

    Any opinions on manufacturers of filters? K&N boasts, but I'm not sure and they are ridiculously priced.

    Discuss...

  • ignorant

    Sept. 18, 2008 9:45 p.m. ignorant UberDork

    for a turbocharged vehicle.. the more surface area the better. Open up both ends of the turbo, i.e. remove all restrictions and it'll go a good deal better.

  • Sept. 18, 2008 10:30 p.m. SVreX UltraDork

    That's the point.

    I want to pump as much air through this thing as I can.

  • gamby

    Sept. 18, 2008 10:50 p.m. gamby UltraDork

    Then cone is your answer--unless you can fab a big airbox for a big panel filter.

  • Sept. 19, 2008 5:35 a.m. SVreX UltraDork

    I've got plenty of space.

    Are the cheapo cones worth anything?

  • Sept. 19, 2008 12:42 p.m. 93gsxturbo New Reader

    Its tough to screw up a cotton/gauze filter but yet aftermarket manufacturers have figured out how. There was a problem with the cheappies with the inverted cone in the center of the end coming loose and going into a few turbos on the cold air kits for the 6.5 Detriot powered GM trucks/SUVs. Whether or not you want to roll the dice on one is up to you.

    Cruise the local swap meets for a used genuine K+N, they are $5-10. I always buy every one I find since I can always find something turbocharge to stick it on.

    An upgrade for the Cummins trucks is a BHAF, big honkin air filter, which is the size of a 5 gallon bucket. Its a round paper filter.

    Round filters have much more surface area than flat filters.

  • Jack

    Sept. 20, 2008 9:26 a.m. Jack SuperDork

    Building a box was tough, so I used a huge cylindrical filter, 2.5 times what K&N suggested (surface area) for the size engine. The filter I picked had a bellmouth entry into the intake pipe, so good flow is pretty much a given, even if the air comes more from one side of the filter or another.

    Jack

 

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