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Thread: B&M Blower

  1. #1

    Default B&M Blower

    Hi guys. I've just bought an engine. It came with a B&M blower. How do I tell what it is? There's no numbers or markings on it. Does anyone have a pic of a 420 and a 250 Mega Blower? I might be able to see which one mine is. Also, it has a serpentine belt on it, and was wondering if I could change it to a belt like on a 8/71 blower. Thanks for any help.

  2. #2
    Join Date
    Dec 2009


    Contact Weiand Tech Service (LINK).
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  3. #3


    I'm in Australia, they're asleep when I'm awake. LOL!

  4. #4


    If it has bolts going through the case, it's a 144 or 142. If it can fit two carbs on top and flat, it's a 250.
    If it has mount bolts only on the lower flange and only can fit one carb, it's a 177.
    Aside from that, it would be hard to tell the difference of a 420 Mega Blower to a 4-71.
    The 250 Mega Blower is flat compared to a 6-71, and it can fit two carbs. It's about as long as a 6-71, just not as tall.
    Last edited by Gen2Van; 02-06-2019 at 12:40 AM.

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