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Base Timing Spark Advance....

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Old 08-11-2018, 06:57 PM
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Base Timing Spark Advance....

Should this change, after replacing the harmonic damper? Did mine a few weeks ago, always had the base timing at 8deg. Today finally got the timing light out, and my base advance was at 10deg, so i loosened up the dist, and got it back down to 8deg. That's what i have it set to in the ECM prom.
Thanks!
Old 08-11-2018, 07:04 PM
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Re: Base Timing Spark Advance....

I would compare old balancer to new to see if there was a change. Measure between key slot and timing mark to see if it shifted. with age it can shift.
Chris
Old 08-12-2018, 09:48 AM
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Re: Base Timing Spark Advance....

Put the timing where the car runs the best.

Changing the damper didn't change the timing itself; it just changed what your light lied to you that it was/is.

If it RUNS good, it IS good. If it ran as good as it could before, and you changed it, it is now, BY DEFINITION, not as good. Put it back.
Old 08-12-2018, 04:37 PM
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Re: Base Timing Spark Advance....

Originally Posted by kaydoe
I would compare old balancer to new to see if there was a change. Measure between key slot and timing mark to see if it shifted. with age it can shift.
Chris
well a little too late for that! im pretty sure i compared the old and new dampers side by side, and they looked the same. damper is keyed onto the crank, and i never rotated anything, so shouldnt have moved. I never actually measured the base timing before the replacement, just from my notes that i had set at 8deg. im now thinking that maybe it wasnt really at 8 before the swap.....the dist could have moved since the last time i actually checked it.
Old 08-14-2018, 02:53 PM
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Re: Base Timing Spark Advance....

What kaydoe is stating is that the outer ring of the old balancer that has your timing mark on it may have shifted so what you thought was 8 degrees was not 8 degrees and now the new balancer which should be correct is showing your true timing.
Old 08-14-2018, 07:03 PM
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Re: Base Timing Spark Advance....

Originally Posted by T4Turtle
What kaydoe is stating is that the outer ring of the old balancer that has your timing mark on it may have shifted so what you thought was 8 degrees was not 8 degrees and now the new balancer which should be correct is showing your true timing.
Ok, thanks, now i got that, kinda makes sense. The old balancer had some junks of the glue/seal, that holds the 2 halves together, missing. So it very might have shifted on me, but at least it was only off 2 deg........i had made a post about my balancer a few months ago, and thus i was instructed to replace it!
Old 08-16-2018, 09:12 PM
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Re: Base Timing Spark Advance....

Many, many years ago when my car had a SBC under the hood, it ran great with 44* of total timing. It wasn't until I installed a degree wheel and located TDC that I found out the timing mark was off 8*. My 44* was actually 36*.

I installed an adjustable timing pointer to correct the mistake.
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