Spark advance at idle
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From: Macedonia ,OH
Car: Formula
Engine: 6.0 LSX
Transmission: 4L60E
Axle/Gears: 9 Bolt 3:27
Spark advance at idle
I have it set at 6* and it shows 12* when plugged in on my Tech 1 is this right? i thought it was more like 14-16
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From: Oakdale, Ca
Car: 89 IrocZ
Engine: L98-ish
Transmission: 700R4
Depends on what parameters the ECM sees and determines to try to set it at.
You just put in a new cam, right? Probably less vacuum, could be interpeted as being a bit under load and the ECM retarding the timing some until the engine starts to get wound up.
This is where tuning your EPROM would become to be a big advantage, in the old days you could adjust the distributors, change weights and springs to curve your timing and advance, now you're at the mercy of what GM gave you ad tha parameter it's set to run with.
You just put in a new cam, right? Probably less vacuum, could be interpeted as being a bit under load and the ECM retarding the timing some until the engine starts to get wound up.
This is where tuning your EPROM would become to be a big advantage, in the old days you could adjust the distributors, change weights and springs to curve your timing and advance, now you're at the mercy of what GM gave you ad tha parameter it's set to run with.
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From: Philly, PA
You need to unplug the timing wire before you set the base timing with a timing light. 6* BTDC base timing is a typical spec for a GM FI engine.
The timing your ECM is putting in is IN ADDITION to the base timing. So 6* base plus 12* ECM advance would be about 18* actual at idle. Again, that's pretty typical for an 80s era FI motor.
The timing your ECM is putting in is IN ADDITION to the base timing. So 6* base plus 12* ECM advance would be about 18* actual at idle. Again, that's pretty typical for an 80s era FI motor.
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From: Macedonia ,OH
Car: Formula
Engine: 6.0 LSX
Transmission: 4L60E
Axle/Gears: 9 Bolt 3:27
Originally posted by Damon
You need to unplug the timing wire before you set the base timing with a timing light. 6* BTDC base timing is a typical spec for a GM FI engine.
The timing your ECM is putting in is IN ADDITION to the base timing. So 6* base plus 12* ECM advance would be about 18* actual at idle. Again, that's pretty typical for an 80s era FI motor.
You need to unplug the timing wire before you set the base timing with a timing light. 6* BTDC base timing is a typical spec for a GM FI engine.
The timing your ECM is putting in is IN ADDITION to the base timing. So 6* base plus 12* ECM advance would be about 18* actual at idle. Again, that's pretty typical for an 80s era FI motor.
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