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  1. #1
    inteljd's Avatar
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    Question 5 inch fresh air intake

    Ok so itís my turn to ask if anyone out there has considered running a 5 inch fresh air intake system. Iíve had my 4 inch custom intake for about 2 years but now Iím jumping to a 5 inch. To me itís important to have free flow air movement through the ski, with all of the mods out there such as RUDE SC's, direct exhaust and higher RPMís I want to make sure that I donít restrict the incoming airflow.

    So I leave to all of you for your opinion: How important is it to have unrestricted airflow?



  2. #2
    JFizzleJR's Avatar
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    I believe it has been concluded that 5" hose results in a loss of optimal velocity caused by too much volume in the hose in order to be able to maintain a greater efficiency than the 4" intake. Take THAT engineermike and WOT! (only 2 technical smarty pants people that I could think of)
    Last edited by JFizzleJR; 03-24-2008 at 08:41 PM.

  3. #3
    The ski's have taken a "backseat" to the Corvette DarthAWM's Avatar
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    I don't believe that with the cramped interior of any ski hull that unrestricted is possible. The point is to reduce restriction. I can't see how 4 in intakes are unnessisarily restrictive. The main points we could or would have restrictions at are filters and flo-rites mostly flo rights the best next step would likely be to increase surface area of the flo rite material i.e. to make a folded air filter setup like a K&N.

  4. #4
    The ski's have taken a "backseat" to the Corvette DarthAWM's Avatar
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    Also we are only talking about 350-400cfm at WOT 4" is more than enough room, heck the stock intake on my 64 chevelle funnels 650cfm through a hole the size of a .50 piece

  5. #5
    Jeepster's Avatar
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    Bigger is not always better, you got to keep the velocity (flow speed) at which the air is sucked in, just like in an exhaust, too big and you are actually loosing performance.

  6. #6
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    Whats important is the transition from large to small. You want a smooth flow.

    If you go larger then required, you have to deal with a larger change and therefore most likely a longer intake tract. Think of how Velocity stacks work (reducing the "K" factor) for entrance losses and it will become clear that at some point a maximum is reached.


    Shawn

  7. #7
    cbrich's Avatar
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    Quote Originally Posted by DarthAWM View Post
    Also we are only talking about 350-400cfm at WOT 4" is more than enough room, heck the stock intake on my 64 chevelle funnels 650cfm through a hole the size of a .50 piece

    But your chevelle is carbureted, which is basically a glorified venturi injector.

    When pressurized water enters the injector inlet, it is constricted toward the injection chamber and changes into a high-velocity jet stream. The increase in velocity through the injection chamber results in a decrease in pressure, thereby enabling an additive material to be drawn through the suction port and entrained into the water stream. As the jet stream is diffused toward the injector outlet, its velocity is reduced and it is reconverted into pressure energy (but at a pressure lower than injector inlet pressure).

  8. #8
    inteljd's Avatar
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    Too many PM's to ask me how I'm doing this so here's an illustration of my intake. By the way the sound of the exhaust and the sound that you hear from the front of the RXP hood in unisun create a unique tuner sound. You actually hear the SC screaming!!
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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  9. #9
    Moderator The Bandit's Avatar
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    Quote Originally Posted by inteljd View Post
    Too many PM's to ask me how I'm doing this so here's an illustration of my intake. By the way the sound of the exhaust and the sound that you hear from the front of the RXP hood in unisun create a unique tuner sound. You actually hear the SC screaming!!
    love that hood and color.

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