Chip, I'd be worried if it wouldn't suck oil with 3 quarts, since 5 is usually the capacity and 1 is usually working its way around the motor while its running, so that doesn't leave much room for sloshing and accidental low oil levels. Most vehicles I have experienced will pull oil with less than two quarts in the pan. If you have a deep pan and can run six quarts without bad windage problems then that may be ok. The oil capacity of the pan is the point where the oil is close enough to the crank that it gets whipped into a froth from the air flow around the crank, which is bad.

I really think you should find the right pickup/pan combo for this motor, it's not worth finding out the hard way.

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