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Old 06-17-2016, 12:19 AM   #247
R2
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Quote:
Originally Posted by Matt@Cosworth View Post
I tweaked the DI timing ever so slightly on the 1.3 tunes to match the revised cam timing - it was worth about 2 bhp at most
I'm starting to look at DI timing and I'm struggling to understand the theory behind advancing or retarding it. To me it makes sense to advance it so the fuel has the longest time to evaporate and cool the charge and minimize knock, but I understand there is the problem with impingement on the piston if it's too early. Secondly, where does the slight improvement in power come from? It doesn't seem like VE will change with DI angle, and assuming ignition timing is the same, how does one injection angle make more or less power than another?
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