Big block chevy leakdown or fuel system info.

Discussion in 'InsideTopAlcohol.com Tech Questions' started by Outlaw Funnycar, Sep 9, 2018.

  1. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    Back in my dad's mud racing days, they ran Mallory Super Mags and when the "mag pin" would shear, it would go from running normally to shooting flames out of the headers. I really haven't been around many Super Mags, nor did I ever get a deeper explanation of the problem (was a kid at the time). I would assume it has to do with the trigger and points.
     
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  2. SoDak

    SoDak Active Member

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    The roll pin that connects the gear to the shaft is the common one to shear or partially shear and this causes the ignition timing to retard. Plenty common in the BBC world. I broach the gear and key the shaft so this is not a concern for our engines anymore.
     
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  3. blownapex

    blownapex Member

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    has the blower been restripped
    i restripped a 14/71 and it ran real weird
    i put the rotors in swapped (left for right)
    fuel was coming out aerated nozzles
    when i called bill barrett he imidiatly knew what i did
    thats the last one i stripped
     
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  4. Outlaw Funnycar

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    Rotors have not been restripped. And the mag is vertex from Joe hunt. 4.2 amps
     
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  5. wagspe208

    wagspe208 Member

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    1) Boat guys are idiots... I know... I am one
    2) A 110 is TONS of fuel for something with no blower. (not disrespectful... )
    3) Ignition... is it an MSD? If so, they are polarity sensitive for the pickup... if a crank trigger for sure..... if a distributor... I believe so...
    How do I know this???
    See number 1
     
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  6. Outlaw Funnycar

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    Lmao. I was wrong about the blower its an 8-71 Littlefield not 6 not that it matters much. I've got it at 10% over and figured out the pump flows good numbers and is not far off from factory specs. I forgot to put the 140 main back in the bv. My fault though and that's another reason why the square barrel valve is going away in lieu of k valve I understand them a lot better. Had a poppet that was sticking somehow. Took it all apart and it had a gouge inside that was making the spring hang up on I suppose.
     
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