73-87chevytrucks.com

73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: slammed79 on March 02, 2009, 07:45:59 pm

Title: Left Bank Backfire
Post by: slammed79 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

Title: Re: Left Bank Backfire
Post by: VileZambonie on March 02, 2009, 07:49:56 pm

Check your plugs, wires and distributor cap. Check your timing.

Title: Re: Left Bank Backfire
Post by: slammed79 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.

Title: Re: Left Bank Backfire
Post by: VileZambonie 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.