A/F scoops?

Discussion in 'Pit Buzz' started by Will Hanna, Nov 20, 2007.

  1. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
    Staff Member

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    How much would an A/Fueler lose or gain without a scoop?

    I remember Stark saying it was worth about a tenth when he put one on back in Houston.....92 or so. That was when Dale Armstrong and Bob Brooks were helping him quite a bit.

    A scoop has to make enough horsepower to overcome the parasitic drag losses associated with it. they say a pro stock scoop robs 80 hp at 200 mph. obviously it makes more than 80 hp, hence they run them. is it safe to assume an a/f scoop robs in the neighborhood of 150 hp or more, depending on design?

    Art Gallant ran awful fast for a long time with an enderle hat.

    I'm sure some of scoops work better than others.
     
    #1
    Will Hanna, Nov 20, 2007
  2. fuelslut

    fuelslut New Member

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    don't forget about automan's cereal box.
    [​IMG]
     
    #2
    fuelslut, Nov 20, 2007
  3. dave hirata

    dave hirata Member

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    re: scoops

    would'nt that "ottoman" scoop look sweet out the w/shild of a funny car? it would look good as my gutters on my house too.
     
    #3
    dave hirata, Nov 20, 2007
  4. Darren Smith

    Darren Smith New Member

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    That thing looks like Godzilla's Mailbox!:eek:
     
    #4
    Darren Smith, Nov 21, 2007
  5. nitrohawk

    nitrohawk New Member

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    No Scoop????

    Will
    When making license runs to get Chrisman's license the scoop craked real bad.
    We had already met the minimum license requirments so I desided to go ahead and make a run without the scoop rather than have to come back another day.
    It did not seem to make any difference in the incremental times but started to drop cylinders at about the eight. On prior runs it had not dropped cylinders. Guess my conclusion was that until the car gets up to 190/200 mph it probably has no real negative effects.
    Scoops are very interesting as there are cars out there with small openings up to the Automan size that seem to work ok. But we all know there has to be one size that is best. Maybe it depends on the size in sq. inches of the injector blades. The actual cfm requirments of the engine is much less than all of the current injectors will pass. We all know the effects of a positive manifold pressure.
     
    #5
    nitrohawk, Nov 21, 2007
  6. johnny ahten

    johnny ahten Member

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    Dave, I love it! That should stir the pot!

    We all have stuck our hands out the window on the freeway at 60 mph. Imagine trying to hold a scoop out of a window at 250+mph.
    Johnny
     
    #6
    johnny ahten, Nov 21, 2007
  7. fuelslut

    fuelslut New Member

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    think about the siphoning effect across the top of the injector as the car speeds up too. i see alot of drag boats with the scoops facing backwards.
     
    #7
    fuelslut, Nov 21, 2007
  8. bob szabo

    bob szabo FC / altered

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    hood scoop size

    We did an article for IHRA DRM on hood scoop size. You can down load it for free on the site:
    www.racecarbook.com
    click on ARTICLES on the left column
    look up Hood Scoop Size
    The info in the article should add more info to the size resolution issue.
    Bob Szabo, author of Fuel Injection Racing Secrets & 5000 Horsepower on Methanol
     
    #8
    bob szabo, Dec 12, 2007
  9. WANNABE

    WANNABE New Member

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    On Automans smaller cereal box, (Woods dragster), he had a pressure sensor at the base of the scoop and top of the injector. the thing would show over 2 pounds of boost from around 400 feet on. Almost got to 3 psi. A small blower. (Could explain the dropped holes.)
    And no. Dragboats do not run the hat backwards. Those are the circle boats that run 5+ mile courses and often get washed down by the boat in front and in the corners. Predominately the K boats. (Blown alcohol.) Rather than swamping the engine, they flip the hat around and let the driver get soaked, and the engine only wet on the outside.
    B-Pics Magazine.
    But I have heard of pro stock style cars running without a scoop, and the draft will pull gas right out of the carbs and wash the windshield and top of the car with fuel.
     
    #9
    Last edited: Dec 17, 2007
    WANNABE, Dec 17, 2007

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