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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: bigjoe62b on July 02, 2014, 12:59:29 pm

Title: Ignition timing on a big block
Post by: bigjoe62b on July 02, 2014, 12:59:29 pm

Hi, I have an 86 stepside with a 454 and a th350 gearbox. I was wondering about the ignition timing marks on the stock cam cover. I see the 0 for top dead centre but for setting the ignition timing how would I go about setting the idle timing on it. I was going to run about 12 -13 degrees of idle timing.
(http://img.tapatalk.com/d/14/07/03/eta5u2e7.jpg)Thanks guys


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Title: Re: Ignition timing on a big block
Post by: ehjorten on July 02, 2014, 01:16:17 pm

Your timing tab should have numbers for -0-, -4-, -8-, -12- on the upper side, or BTDC.  I believe every mark on the timing tab is 2° and ever peak of the saw-tooth point is 4° apart.

Alternatively, you could use a dial-back timing light or put a timing tape on your balancer.

Depending on the condition of your harmonic balancer your TDC mark may or may not be accurate.

Title: Re: Ignition timing on a big block
Post by: bigjoe62b on July 02, 2014, 02:36:22 pm

Oh yeah. I couldn't see the marks on it but I can see them now.


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