Originally Posted by Jon Kerr

I'm running an OS EB Mods V-Spec .21 in my 8IGHT. I've got about 3/4 gallon through it. So far every race day, I've gone through a P3 (the plugs EB says to run in the engine) plug. And they're not burning up. The elements are breaking. Twice I've had them break in the middle of a main where the car will stall, then when it won't start again, we pull the plug out and the element is broken. Every other time, it's after the main, I go to put after run oil in and check the plug and it's broken. The engine runs great, but what's the deal? I'm still not really clear on the different plugs. Is a higher number hotter or colder? Would you run a colder plug in hot humid weather? etc... It's been really hot and humid around here lately (100º+ and very humid) so I don't know if the P3 is too hot of a plug for that kind of weather or what. I was running O'Donnell 30% and I've started running Nitrotane 30% and it's done it with both fuels. I've got a bunch of Orion Turbo 6 plugs that I could use. I ran one in a qualifier and not having time to tune the needles, it ran like crap. Would that be a better plug? Is it a hotter or colder plug.

Sorry for the rookie questions. Still trying to wrap my head around tuning nitro engines.