Originally Posted by
nitrodude
Usually you dont change the temp range of the plug for the temperature, unless its really hot. Just use the plug that runs good for your engine and stick with it, regardless of the weather. I suspect that the problem you were having had nothing to do with the type of plug, probably had to do with the tune of the engine.
Not realy true.
The ignition timing is depending many factors like head clearance, nitro content, plug number and outside temperature.
If one of the factors is changing and it goes off the ideal ignition timing you should compensate with another. Most of the times the nitro content is compensated with the headshims and the outside temperature is compensated with the plugnumber.
And yes changing one of these factors without a reason will cause a different operating tamperature due a shifted ignition timing.
If the temperature of the engine is too low and the engine does not run properly then the ignition timing is too late.