On cranking advance...
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Joined: Jun 2009
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From: Istanbul, Turkey
Why is cranking advance less than idle advance on MS2?
I had a conversation with Dimitris about this a few months back, and he was concerned about starter kickback.
But, in my experience, a higher (to a point) cranking advance means quicker starts.
If you were to deliberately retard the advance on a distributor setup, you would see that while cranking rpm increases due to less resistance, it takes longer for the engine to fire.
I mean, on a conventional distributor engine, cranking advance = idle advance.
And, on vacuum retard setups, cranking advance is even higher than idle advance - there's little or no vacuum while cranking, and once the engine is idling, manifold vacuum retards timing, allowing to increase to a preset value as vacuum decreases with the opening throttle.
So, could you guys please explain why I should not raise my cranking advance to 16 degrees from the initially preset 6 degrees?
I have been experimenting with 12 degrees, with much improved results so far..
I had a conversation with Dimitris about this a few months back, and he was concerned about starter kickback.
But, in my experience, a higher (to a point) cranking advance means quicker starts.
If you were to deliberately retard the advance on a distributor setup, you would see that while cranking rpm increases due to less resistance, it takes longer for the engine to fire.
I mean, on a conventional distributor engine, cranking advance = idle advance.
And, on vacuum retard setups, cranking advance is even higher than idle advance - there's little or no vacuum while cranking, and once the engine is idling, manifold vacuum retards timing, allowing to increase to a preset value as vacuum decreases with the opening throttle.
So, could you guys please explain why I should not raise my cranking advance to 16 degrees from the initially preset 6 degrees?
I have been experimenting with 12 degrees, with much improved results so far..
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