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Discussion Starter #1
General question regarding spark plug gap on any gasoline engine, not necessarily the LSx:

If you are given a range for gapping a certain plug, like from .038 to .042, if you gapped one at .038 then gapped another at .042, would one be hotter or cooler than the other or offer better combustion? Or is the .004 difference too small to have a noticeable effect?
 

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TR6 plugs with a .55 gap are good plugs for low-mid boost applications. The higher the gap the colder the plug I believe is how it works. You're not going to get a performance increase from changing something like the gap on a plug on a stock engine. Gap differences are mainly to keep the cylinder from detonating prematurely.
 

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Discussion Starter #3
Thanks for the info Crabhart. The application I had in mind was for my Harley, with a stock fuel-injected v-twin engine plus the stage one kit and pipes. I put new plugs in it a couple days ago (getting spring fever:)) and the gap is .038 to .042. I didn't know if it would make much difference if I gapped them at the low end or the high end. The larger gap would make for a longer spark travel, but I didn't know if that would make the spark cooler or maybe offer a little better combustion since there would be more spark exposed to the air/fuel mixture. I gapped both at .038 which is what I ran the last set at. I want to experiment with a larger gap and see if I could tell a difference but it's too cold here right now to get it out and play with it.
 

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I live about 20 mins away from the Harley plant in York, PA. they are out there with their picket signs. According to the news, the company is asking them to pay some towards their healthcare, and a 4% pay raise over 3 years, and new hires are to make less $$ at hire than the "oldtimers". They have been on strike now like 3 weeks.
 

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I heard a little bit about it but I haven't kept up with it closely, so I really don't know enough about the situation to comment on it. There are two sides to every story though.
 
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