Thread: Ignition Timing
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Old 08-30-2007, 11:03 AM
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bobcowan bobcowan is offline
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Location: Colorado Springs, CO
Cobra Make, Engine: Backdraft, supercharged Coyote
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If I read that right, you 14* of intial, and 30* of advance, for a total of 44* of ignition advance. That's a lot of advance. Most SBF's peak out at around 34-36* total. More than that costs you power. Less than 30* and you become very inefficient, and lose power.

I would set initial at 10*, advance at 24*, and continue to mix fuel.

You built an engine with 12.5 SCR, and you live at sea level. With that much cylinder pressure you need high octane fuel. There's really no way around that. It might be cheaper to buy premium pump gas and add toluene to raise the octane.
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