3000GT/Stealth International Message Center - View Single Post - Detonation vs. Pre-Ignition

bluemax_1 · 10-26-2005, 08:48 PM

IPO,

I think klamathpro is right. The reason for plug heat ranges is because there is an optimal heat range for the spark plug in the engine. If the plug is not a cold enough range, it isn't conducting enough of the heat it absorbs from the combustion and can either create a hot spot for pre-ignition or potentially burn the electrode tip.

While colder plugs are more effective at conducting heat to the head, it is the little heat that they've absorbed to keep them in proper operating temp range that they're supposed to conduct away. Their effect as a heat sink to draw heat out of the chamber is much less significant.

Too cold and the plug doesn't stay clean vaporizing/burning off fuel that comes in contact with it and it will start to develop carbon deposits, which of course can lead to the potential for hot spots and pre-ignition and if the gap is small enough, carbon deposits eventually bridging the gap.

Max

10-26-2005, 08:48 PM	#24 (permalink)
bluemax_1 July 2003 Join Date: Jul 2003 Location: MI Drives: '94 VR-4 Trader Rating: (16)	Re: Detonation vs. Pre-Ignition IPO, I think klamathpro is right. The reason for plug heat ranges is because there is an optimal heat range for the spark plug in the engine. If the plug is not a cold enough range, it isn't conducting enough of the heat it absorbs from the combustion and can either create a hot spot for pre-ignition or potentially burn the electrode tip. While colder plugs are more effective at conducting heat to the head, it is the little heat that they've absorbed to keep them in proper operating temp range that they're supposed to conduct away. Their effect as a heat sink to draw heat out of the chamber is much less significant. Too cold and the plug doesn't stay clean vaporizing/burning off fuel that comes in contact with it and it will start to develop carbon deposits, which of course can lead to the potential for hot spots and pre-ignition and if the gap is small enough, carbon deposits eventually bridging the gap. Max __________________ 1994 3000GT VR-4. Hobbies... what are hobbies? Oh, those things people do when they're NOT working on their cars?