Really quick timing question

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Jun 13, 2009 | 11:49 PM

DaJesterMan

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Racer

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Really quick timing question

Hey guys,

I have a 427 BB and I can't find anywhere what the initial and mech. advance should be set too? I am not running a vaccum advance unit.

See, I told you that was a quick question...

TIA
-ks

Jun 14, 2009 | 01:21 AM

427Hotrod

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From: Corsicana, Tx

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Without knowing a single thing about your combo...the only thing I can suggest is to start with 36* total timing. Might do better with 38*-40*...but that's up to the combo.

Tuning dist for base timing to be around 20-22* and limit it to the 36* total or so will really wake up low speed manners.

JIM

Jun 14, 2009 | 10:08 AM

Jeff_Keryk

Drifting

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From: Los Gatos CA

My stock 68 L36 distributer has 16* mechanical advance (32* @ crankshaft). The initial setting is 4*, so total is 36*. I being it in a little faster; all in by 2800 RPM. It sounds like you have an aftermarket distributer. I would get a timing tape and measure.

Jun 14, 2009 | 11:01 AM

Ironcross

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From: Taylor Michigan

solid lifter engines normal initial lead is 10 degrees and range from 8-14 according to a Bill Thomas tune up chart.

Jun 14, 2009 | 11:23 AM

DaJesterMan

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Racer

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i guess this is a little more complicated than i thought...

i have no information on the heads, cam, or compression ratio. so i guess ball park would be what 427HotRod suggested... 20-22 initial, 14-16 mechanical, all in by 2800

i thought these were reasonable numbers but i wanted to double check...

-ks

Jun 14, 2009 | 11:30 AM

...Roger...

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From: Dayton, Ohio

You can also go out and drive and bump the timing a little at a time until it just starts to ping and then back it off until it doesnt and then check your timing and see where you are.

Jun 14, 2009 | 12:04 PM

DaJesterMan

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Racer

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i have never heard an engine ping before, is it loud? what does it sound like?

Jun 14, 2009 | 12:54 PM

7T1vette

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From: Crossville TN

Like there is a bolt rattling around in one of your cylinders. Not good.... Just set the mechanical advance for 34-36 deg {max, with vacuum advance removed and line plugged} all-in by 3000 rpm. Hook up the vacuum advance system to verify that you get a 'total' advance around 52 deg and test it to verify no pinging under load. If it idles OK, don't even worry about timing at idle; just fine tune the idle mixture and idle speed.