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Old 12-23-2005, 12:40 PM   #1
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Default Blown timing

What should ignition timing be for a L67?

I've seen 11* at best in my 92 with a Hypertech chip.
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Old 12-23-2005, 12:43 PM   #2
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I've seen as high as 20 with my Jet, pre-porting/lean conditions I have presently.
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Old 12-23-2005, 01:00 PM   #3
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Is timing shown before or after any KR?
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Old 12-23-2005, 01:02 PM   #4
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If you have KR, it'* subtracted from the timing number you see.
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Old 12-23-2005, 01:02 PM   #5
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Mkay, so what could cause my low timing?
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Old 12-23-2005, 01:08 PM   #6
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IAT temps, KR, octane, and even TCC slip if I recall. I'd have to dig into the FSM to find all the stuff that affects timing advance.
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Old 12-23-2005, 02:22 PM   #7
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IAT is a few degress from ambiant, KR is a couple degrees sometimes at WOT, sometimes none at all. Slip seems to be normal, last I checked.
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Old 12-23-2005, 02:31 PM   #8
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Actually if your seeing KR, its not a 1to1 ratio. I know my numbers are little off, but its more like for 1*of KR you loose~ 1.65-2.15* of timing.

The lowest timing advance I have seen is 8*, and that was an unmollested PCM with 14* of KR so that tells me that KR may fall on as a stair step.

Maybe you can scratch all this-this may only pertain the series 2
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Old 12-23-2005, 02:46 PM   #9
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IIRC stock timing is set at 12*... That means if you have 0 KR at WOT you will have 12* of timing. You have to have a chip to add more timing. 20* seems really high for an 'universial' chip and seems kinda dangerous to me unless I had control over it. Also 3* of timing = about 1 lb. of boost.
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Old 12-23-2005, 03:24 PM   #10
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Right now if i go at WOT my timing go down to 7, and the car "die" lost power,

cant find what is doing it, IAT is good, i have no KR at all.
under 7 the car tend to stall. but at idle its good.

(on choke, when the car is cold, the RPM bounce 500-1800.) when the car warm up, it go away.


Ive changed my crankshaft sensor but i need to do the case relearn, ill see after if this solve the problem.


Can a bad PCM do this too? the last scan we made, the O2 sensor test wasnt available.
and some other too.
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