Bug catcher HP limit

Discussion in 'PSI Superchargers Tech Questions' started by Bob sherry, Oct 14, 2020.

  1. Bob sherry

    Bob sherry Member

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    Gday guys it's Australia calling, I was wondering what is a bug catcher capable of making in horsepower? Using a std helix non stripped 871 blower on a 469 cui big block chev on alcohol. Is there a limit that can be made with a Bug?
     
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  2. swsc4133

    swsc4133 Member

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    i would think that it will handle anything that particular blower will want. Someone pointed out to me once that "little bug catchers" went 5's many years before all the big injectors
     
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  3. Bob sherry

    Bob sherry Member

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    Just curious if someone has any figures on a bug or an example on a running car.
     
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  4. Graham Brown

    Graham Brown Member

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    Hi Bob,
    Just to compare with carbs, a Bug Catcher has ~32 square inches of butterfly area, that equates to a 1 x 4 bbl all with 3-3/16" diameter butterflies or 2 x 4 bbl all with 2-1/4" butterflies.
     
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  5. tommyt

    tommyt New Member

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    Does anyone have real world numbers how much can be picked up going from a Bird to a modern hat on a blown alcohol car , with a run of the mill 14-71HH blower ?
     
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  6. a/fd slngsht

    a/fd slngsht Member

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    Several nostalgia top fuel cars run bug catchers... 5.60ish in the quarter...
     
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  7. Bob sherry

    Bob sherry Member

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    Yes used a bug catcher in top fuel myself back in 1988-90, we ran 6.0s back then here in Australia. I was just curious if there is a power limit using a bug and 871 on methanol , maybe someone has done some testing with a bug verses a bird , which would be interesting to know.
     
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  8. Bjs344

    Bjs344 Member

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    I’m going to try something here shortly. Small opening inlet on a 14-71 hhr. If cylinder head flow principals mean anything; inthink people say ports start to back up around Mach .5. For what I’m using that should be around 16-1800 hp on methanol. A bug is bigger than what I have.
     
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  9. Bob sherry

    Bob sherry Member

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    If this is on a running car it should be interesting, I hope you post the results. Mach .5 is a good rule of thumb for normally aspirated ports of which I have spent 40 years of my life playing with, but I must admit I haven't spent any time playing with above atmospheric pressure. I would imagine the air speed would be far higher than Mach .5 . I have flow tested inlet ports backwards by blowing through the port but never simulated boost pressure, it would be a good subject to study in the future. As far as your deal restricting the hat inlet air it should reduce power, but at the same time give you an idea of what the blower really wants. Your results would be very interesting I hope you post them, thanks very much for the info.
     
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  10. Bjs344

    Bjs344 Member

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    All the parts are on the property, just need bolted together.

    Im sure I’ll learn something I wasn’t expecting to but that’s part of the fun

    I’m not trying to go super fast for what I have but there is a little part of me that’s curious about stuffing a bunch of air into the front of the rotor and whether that’s worth anything.

    I think the smallest blower openings are around 9” long for 14.5 od limits? Anybody ever try anything smaller?
     
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