My understanding is that ambient temperature affects it as well.
Hot weather/cold plug and vice-versa. I live in a hot-weather climate but still prefer hot plugs. Honestly if you were to switch out plugs with each gallon for five gallons...I doubt I'd be able to tell you "Oh, this is a medium-hot plug. O'onnell 97 perhaps?" ;-)
I have found it harder to race tune with colder plugs. I like O.S. plugs although I use O'Donnell,Werks, and Kyosho plugs.
For the best 'all-around standard plug, I like O.S #6 (A3). Best all-around turbo I like the P4.
One thing I've always wondered, that perhaps you engine gurus/Jedi's out there can answer: is there any potential adverse affects using different brands of plugs in different engines. By that, if I were to use a P4 in an O.S. engine for a few gallons, then switch to a C6, then switch to a 99, etc. are there any latent effects?
HotRob...how many are you referencing in you response above? I only see the mention of "two" listed in the threads so am obviously missing it. I sure hope so as below is just my backups. I have twice as many extras' I keep are in my pit bag. I actually switch out too often, but it's an impulse buy when I see them on sale.
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