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Old 05-02-2006, 06:46 PM
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A knock sensor only detects knock, and this signal to the PCM means to retard timing. What I was trying to say very early in the AM, without a large enough coffee infusion, is, if there is no knock, the PCM will advance timing until knock is detected than back off.
However, the knock sensor cannot detect higher octane, is is piezo device that generates a signal from a specific resonance from the engine (knock).
Increasing the octane may or may not give you more HP or fuel milage, it all depends on how bad the regular fuel is and if it promotes knock. Less likely to have knock with a slightly higher fuel, but my main question is very simply, "is it worth the price." In this area, mid-grade is ten cents higher than regular.
I ran a few tanks of mid-grade just to see what happened, and nothing, about a one or two tenths rise in fuel mileage.

As for the cylinder head teardowns. Just checking cylinder heads and trying to find a faster way to service them in the future. Right now, the teardown is about 18 hours, new tool might decrease it to around 8 hours.
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