EFI Timing
#1
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Joined: Mar 2002
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I'm planning to do some work on my EFI system map next weekend and I'd welcome any feedback based on others experience:
Engine & Cam Spec is as follows:

At the moment it's running very basic 10 degree initial advance, maxing out at 30 degrees at 3200, along with AFR targets at 12.5 for WOT above 3400, rpm based only
(The 750 & 1100 rpm idle advance numbers are necessary to manage idle speeds. I will finesse it next time, but basically the hilborn setup I have is hard to shut down the airflow any further)

Questions
Engine & Cam Spec is as follows:

At the moment it's running very basic 10 degree initial advance, maxing out at 30 degrees at 3200, along with AFR targets at 12.5 for WOT above 3400, rpm based only
(The 750 & 1100 rpm idle advance numbers are necessary to manage idle speeds. I will finesse it next time, but basically the hilborn setup I have is hard to shut down the airflow any further)

Questions
- Max advance - is 34 degrees a safe number, or 32 a safer bet?
- Is 12.5:1 a decent WOT AFR ratio? Or should I shoot for maybe 12.2? (It is an NA motor, not blown)
- And is a midrange 13-14 ratio for cruising decent? I would like cruise fuel consumption to be as efficient as possible to give me a decent range.

#2
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Joined: Aug 2010
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From: Cape Coral FL
35 deg timing has been safe on every alum headed big block that I have had on the dyno
I don't think the engine would ever know the difference between 12.2 and 12.5 AFR
I wouldn't lean it out too much at cruise, that is close to where it will be making max torque and will require fuel there.
I don't think the engine would ever know the difference between 12.2 and 12.5 AFR
I wouldn't lean it out too much at cruise, that is close to where it will be making max torque and will require fuel there.
#4
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Joined: Jun 2009
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From: Chicago
you cant get better resolution than 3900 and then 6000?
At lower rpm you should be running more timming imop but I have no experience with N/A
Maybe this will help even thou i`m blown ?
I use the large map for better resolution.


At lower rpm you should be running more timming imop but I have no experience with N/A
Maybe this will help even thou i`m blown ?
I use the large map for better resolution.


#5
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