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Tim_Nowicki's avatar
Tim_Nowicki
Explorer
Jun 10, 2013

New Crate Engine 454 up and running

Little over a month ago my 1991 pace arrow blew the engine. Finally got it up and running again with a new crate engine. Just about dialed in now.
One problem: seems to be backfiring thru the TBI. This happens under hard acceleration with the RPMS up past 3000 only. Once it hits high gear it smoothes right out. Feels like a slight miss. Adjusted timing with no change. Idea's from anyone??? thanks

Tim
Class A
  • Stim's avatar
    Stim
    Explorer
    Jun 11, 2013
    Has anything been done to the throttle body or was it just removed from the old engine?
    T B's have a problem with an internal regulator getting weak and with less fuel pressure they can backfire.
    The regulator was easy to replace without removing the T B (IIRC)and was available at regular auto parts stores the last time I replaced one.
  • jmanatee's avatar
    jmanatee
    Explorer
    Jun 11, 2013
    did you use good wires? The 454 is susceptible to cross fire on the wires.

    Drive it at night with the cover off and look for arcing.

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