All my engines are Evolution, I own a .46NT, a .46NX and a .60NX. I run a O.S.#8 short plugs in all of them and I have no problems at all. I only use the stock long plug for the engine break- in, then after that I toss it in the trash and put the O.S. # 8 short plug in.

If you have any questions, look at the graph below... it will give you an idea what to use.



I run a #8 so my engine won't over heat when the weather temps hit 90*. My Evolutions don't like hot and humid temps with a #3, so I run the #8... I've had less "Dead Sticks" as a result.

A short plug or long will not make a difference on how the engine runs from my experience.

I hope I helped.