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copbait73 copbait73 is offline
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Join Date: Nov 2003
Location: Chesterfield IN
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Originally Posted by DonE View Post
IMO, if you are looking to really tune your motor, you are going to have to experiment a bit. I tried about 4 different plugs until I ended up with NGK BKR9EIX. The environment these plugs have to perform in is incredible and when you add boost and timing, you can run into real problems fast. Too hot of a plug and you risk detonation - too cold and you loose power. If you have CDI, you will benefit by using a rare earth metal like Iridium - very hot spark (not plug, the spark). These are large (and old) combustion chambers with two big valves, high pressure and high turbulence that need a hot powerful spark for peak performance.

Also, you'll need to experiment with gaps. I set mine to .032, starting at .025.

Good luck.
Don, you are twin plugged plus you obviously did a lot of test and observation.
Did you notice any patterns top plug to bottom plug or cylinder to cylinder?
Could you or did you disable to bottom row?
Old 03-03-2010, 01:39 PM
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