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Timing question. Ignition curve on stock OB.

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Old 02-20-2012, 09:38 PM
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3000teeth
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Default Timing question. Ignition curve on stock OB.

Hi all,

I'm setting my own timing on my stock '79 and I'd like to figure out what the ignition curve is supposed to look like. Anyone have a graph, or if not, any opinions on what degree idle timing should be set at, and what the advance timing should be at what RPM?

Any help is greatly appreciated.

Thx, -T
Old 02-20-2012, 11:39 PM
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jpitman2
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Is it not in WSM? From other engines whose curves I have seen, I would expect it to rise fast, but peak by about 3k rpm. Will have to look this up tonight now...
jp 83 Euro S AT 54k
Old 02-21-2012, 08:59 AM
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Dave928S
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Tech specs for US 79 call for 31degrees BTDC at 3000 RPM with no vacuum connected to distributor ... can't recall seeing a curve anywhere. If mechanical advance mechanism is working correctly and lubricated you'll get the correct curve and idle advance ... check that it's lubricated as commonly they're neglected.
Old 03-06-2012, 09:29 PM
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3000teeth
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Originally Posted by Dave928S
Tech specs for US 79 call for 31degrees BTDC at 3000 RPM with no vacuum connected to distributor ... can't recall seeing a curve anywhere. If mechanical advance mechanism is working correctly and lubricated you'll get the correct curve and idle advance ... check that it's lubricated as commonly they're neglected.

Cool, thanks. This is helpful.
Old 03-06-2012, 09:34 PM
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jwillman
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Originally Posted by Dave928S
Tech specs for US 79 call for 31degrees BTDC at 3000 RPM with no vacuum connected to distributor ... can't recall seeing a curve anywhere. If mechanical advance mechanism is working correctly and lubricated you'll get the correct curve and idle advance ... check that it's lubricated as commonly they're neglected.
Is the lubrication process outlined in the WSM? Any recommendations on the lubrication?

Thanks
Old 03-06-2012, 09:48 PM
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Ethre
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Is the graph on WSM 28-6 what you want?



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