Author Topic: Left Bank Backfire  (Read 2682 times)

Offline slammed79

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Left Bank Backfire
« on: March 02, 2009, 07:45:59 pm »
I got the 79 on the freeway yesterday morning and got up to speed. At about 3thousand RPM's the left bank started popping back through the exhaust. I peg it to the left bank cause I have headers into cats into muffler into air. No H or X pipe. I've had this exhaust on the small block for about a year and never experienced it before.

 It goes away when I'm under 3k... I'm pretty sure this is a valvetrain issue, but I haven't experienced this one before... Any ideas?


Donnie
74 C10 Long bed 350/SM465 Lowered on 20's

Praise the lowered

Offline VileZambonie

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Re: Left Bank Backfire
« Reply #1 on: March 02, 2009, 07:49:56 pm »
Check your plugs, wires and distributor cap. Check your timing.
,                           ___ 
                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline slammed79

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Re: Left Bank Backfire
« Reply #2 on: March 02, 2009, 07:52:33 pm »
My wires are money, they're less than a year old MSD SuperConductors. I just did the plugs a month ago, though I wouldn't put it past my truck to have fouled one out. The whole tune up is less than a year old and I just timed it today. Still have the problem.
74 C10 Long bed 350/SM465 Lowered on 20's

Praise the lowered

Offline VileZambonie

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Re: Left Bank Backfire
« Reply #3 on: March 02, 2009, 07:53:33 pm »
Wet test your ignition wires and distributor cap (lightly) with a spray bottle and see if it gets worse.
,                           ___ 
                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10