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Old 12-10-2013, 10:28 AM   #13
mad_sb
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Quote:
Originally Posted by arghx7 View Post
Keep this in mind: When your exhaust cam is near its most advanced point, and your intake cam is near its most advanced point, you have early overlap. By early overlap, I mean that as the piston moves upward and the exhaust valve is still open, the intake valve begins opening. This can cause backflow of hot residual gas.

...
Right, and this aligns with what i was seeing... advancing both cams in the problem area makes the problem worse, retarding both makes it better (less prone to tip in knock). With our cam maps, larger numbers on the exhaust side = more retard larger number on the intake side = more advance.

So, of for example the cam maps read 25E 30I in an area you are pron to tip in knock, try 20E 25I and see if it improves.
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