humaxxx, while the above suggestions probably will be good starting points, the optimum curve will be individual for each engine. And if you don't try to find that optimum curve, you'll lose out on HP and also risk pinging. Allow me to recommend my book on the topic. Or if you want, being a fellow Pantera'isti, I'll be happy to send you that section of the book that can help you find the optimum curve.
Regardless, always start conservative, less advance produces less HP, too much advance produces a boat anchor...
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