Std vs hi helix blower wars

Discussion in 'PSI Superchargers Tech Questions' started by NITROBANDIT1, Nov 16, 2012.

  1. NITROBANDIT1

    NITROBANDIT1 LOST IN SPACE

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    ok, say you run a class where this applies., 14.71 hi-helix superchargers are limited to 30%
    overdrive. At tracks with an actual elevation over
    4000 ft, 43% overdrive. Hi-helix blowers are defined
    as any supercharger with a rotor twist greater than
    60 deg. Overdrive limit only applies to 14.71 size.

    would it be maybe a performance advantage to run a std blower with more overdrive, or would it not be enough difference to try? anybody out there tried a back to back comparison between the 2 types to see how much difference there is? any ideas theoretical or otherwise greatly appreciated. thanks for your input
     
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  2. jody stroud

    jody stroud ZOMBIE Top Dragster

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    A good high helix blower at 30% over will will always be better than a standard rotor blower at 30% and higher OD. By the time you turn a standard blower fast enough to get the same boost the rotor speed will be too high. Also the quality of boost is just as, if not more, important the the lbs of boost. 50 lbs of boost at 150deg temp won't be worth a shit. 35 lbs of boost at 100 deg. is better. Plus if TF and FC could run high-helix they would in a heartbeat.
     
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  3. overkill69

    overkill69 Member

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    helix

    High helix produces several hundred more hp at the same boost level. When I switched years ago I lowered the od on the high helix slightly and the car picked up 13mph.

    The only thing better is going from a roots to a screw but the screw cost kills a lot of the fun.

    Blowers have gotten a lot cheaper but engine parts are expensive. An efficient blower makes everything easier. Get the best lung you can afford and adjust everything else around it.
     
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  4. underby6

    underby6 Active Member

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    If the o.d. rule only applies to 14-71's; I'd personally buy an 18-71 high helix and go rotate the earth.:cool: A good screw is exponentially cheaper than a good roots and you never have to strip it, it runs better, and it's easier on parts...if your rules allow you'd be foolish not to consider a screw.

    Brandon Booher
    NHRA TAD #34
     
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  5. NITROBANDIT1

    NITROBANDIT1 LOST IN SPACE

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    Restricted blowing

    unfortunately, screw blowers and anything larger than 14-71 are forbidden. trying to keep class cheap to run i think.
     
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  6. Mike Canter

    Mike Canter Top Dragster
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    When saying 14-71 are you talking case or rotors as being limited or both. Can you use a Superman type blower which as the 14" rotors in a longer case??
     
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  7. NITROBANDIT1

    NITROBANDIT1 LOST IN SPACE

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    Are rules really rules?

    heres the rulebook we have, http://www.wfaseries.com/WFA Rules 2011.pdf it is not specific in nature due to the series is only 3 years old. they are trying to get more cars involved, hence the less specific rulebook. i read it as anything goes with a 14 inch rotor. we do run at some high altitude tracks, salt lake , albq , fallon, so a good pump will go a long ways up there.
     
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  8. AFC357

    AFC357 New Member

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    Again...I agree w/Brandon here...the Screw cost LESS in the long run! When I was racing IHRA TAFC...we all thought the Screw was the "devil"....till ya run one...you wouldnt know:cool: I was stripping our roots every 3-4 runs to keep it "hot"...had to carry 2 of them!! I coild go on and on....but we also had a LOT less detonation issues w/ the screw (cooler intake charge) Our ":cool:blower of the month" roots would make big power...but HARD on parts...and would get so hot you could fry an egg on it!!
     
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  9. overkill69

    overkill69 Member

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    14

    screws are prohibited per the rules. Like Mike said get a 1471 superman and it will go as fast as any altered at 30% OD. I doubt you'll want or need the 43% od.
     
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  10. Cpt Kludge

    Cpt Kludge Member

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    Dan,

    Just put the small blower on it and put 50% in the tank! :cool:

    Steve
     
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