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Old 07-07-2012, 12:18 AM   #55 (permalink)
wstar
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Location: Houston, TX
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Quote:
Originally Posted by DIGItonium View Post
Last week temps were so hot that my oil temps almost touch 240F. I don't think it's pulling timing, but more like limiting throttle. I can feel the car accelerating and hitting a wall as if throttle opening was limited. Physically flooring it has no effect. It's a weird feeling, but I "wstar" made a good point about the ECU limiting throttle opening at low revs. This is one really hot summer.
The throttle limits wouldn't be directly related to heat though, that's just a general thing. This engine does pull timing when things get hot. The ECU is very dynamic about timing. It's looking at very sensitive knock-sensor data and basically always keeping itself just under the threshold of hard knock. So you can think of it as pulling timing in the heat, or adding lots of useful advance when things are cold, but either way it's trying to safely make the most of the available conditions given air temp/pressure, fuel octane, etc.
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