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  1. #1
    primorxp's Avatar
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    At what point is the back pressure of the water box not needed

    So at what point is the back pressure of the water box not heeded. When running a SC it seems to me their is a point you could delete the water box. What say you?


  2. #2
    boost junkie skidoochris's Avatar
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    you would need to do a dyno test to know
    but using the log exhaust mani I would bet a straight pipe would not loose much if any low end
    and at wot it should free up a few ponies

  3. #3
    Matatan tocullo's Avatar
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    There is a few people running straight pipe and is loud as F....K.

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  5. #4
    primorxp's Avatar
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    DB not an issue for a drag ski no pleasure riding 18 lbs of boost 1/4 mile a pass want all I can get out of the top half before I start on pump was thinking a jacketed pipe from manifold to exhaust tip

  6. #5
    imp0ster's Avatar
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    Someone should run zoomies right out the left side of the ski behind their legs.

  7. #6
    West Texas RXP skoepp's Avatar
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    Quote Originally Posted by skidoochris View Post
    you would need to do a dyno test to know
    but using the log exhaust mani I would bet a straight pipe would not loose much if any low end
    and at wot it should free up a few ponies
    I use to run a header with straight pipe and my findings were the oposite.
    The best was a very short muffler - still straight thru.
    It was better down low, in fact almost to much power and could spin prop easy but lost some top end.
    Last edited by skoepp; 11-08-2013 at 07:55 PM.

  8. #7
    primorxp's Avatar
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    Off the line is what I need only do 1/4 mile pulls by the 1/8 at top speed just wanting all I can get out of what I have

  9. #8
    Mothman's Avatar
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    Forced induction engines don't need backpressure.
    If you run straight, run a crap ton of water through the last foot or so to knock down the noise so your ears don't bleed. lol
    I built two shorty boxes and tried each with large amounts of water. The 3.5in exit sounds very good and I ran all but one 1/4 water line and a small pisser through it. Looooots of water...

  10. #9
    boost junkie skidoochris's Avatar
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    it is not forced until over 6000rpm on most sc skis

  11. #10
    captain slow Turbo Retro's Avatar
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    Quote Originally Posted by Mothman View Post
    Forced induction engines don't need backpressure.
    If you run straight, run a crap ton of water through the last foot or so to knock down the noise so your ears don't bleed. lol
    I built two shorty boxes and tried each with large amounts of water. The 3.5in exit sounds very good and I ran all but one 1/4 water line and a small pisser through it. Looooots of water...
    I can tell you that running a turbo with external wastegate and screamer pipe dumping into the exhaust side followed by a ton of water into the exhaust to try and keep it quiet sounds awesome.. and at WOT its just plain sexy..

    downside is that it seems to attract alot of unwanted male attention at the boat ramp and or cafe's

    any waterbox seemed to affect the spooling of the turbo..

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