Spark Plug location

Discussion in 'Performance Mods' started by jaguar, Nov 15, 2011.

  1. jaguar

    jaguar Well-Known Member

    Best location is having it in the center of the head. If you have a head where the plug screws in at an angle then make sure the plug tip is located on the intake side, not the exhaust side. Here's a graph showing the superiority of it being in the center. "Centric" means in the center. "Eccentric" means off center.

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    Last edited: Nov 15, 2011

  2. jaguar

    jaguar Well-Known Member

    I doubted it would make a difference. I always had the spark plug on the exhaust side because the spark plug wire wasn't very long. Now I have a 12" long one from SBP and moved the plug to the intake side (by rotating the head 180 degrees). I was pleasantly surprised at how much more hill climbing power the engine now has. I had been wasting power all this time by incorrect placement of spark plug. Now if I can just find a head for my 55cc engine that has the plug hole in the center.
    FurryOnTheInside likes this.