Spark Plug gap??..some quick help Please
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Teching In
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From: St Louis Mo
Spark Plug gap??..some quick help Please I'm out in the garage doing a plug change and would like to know the best gap on TR6's. I just have your basic bolt on's, Lid,filter, exhaust and so on. No bottle or anything. I thought I'd check here and see what the experts think.
Thanks
Matt
Thanks
Matt
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From: Troy, AL
Re: Spark Plug gap??..some quick help Please It's not critical. The stock gap of .039 works well but for NA applications some might open them up as much as .050. I always ran them at .037 when I was on the bottle but they also ran fine NA and idled great.
TR-55s are generally considered to be the better NA plug (might last a little longer without carbon buildup.)
TR-55s are generally considered to be the better NA plug (might last a little longer without carbon buildup.)
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From: Troy, AL
Re: Spark Plug gap??..some quick help Please I should also add that I have known of people that ran these plugs at .050 and complained of a slightly rough idle. After taking them back down to the preset .039 or thereabouts they reported smooth idleing. Again, at .037 mine idled smoother than stock...no exageration.
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From: Houston
Re: Spark Plug gap??..some quick help Please [quote]Originally posted by vmoore:
<strong>I agree with Colonel. I tried .050 and my idle sucks.. I put it back to stock and the car is smooth.</strong><hr></blockquote>
EXACTLY!!!!!!
wayne
<strong>I agree with Colonel. I tried .050 and my idle sucks.. I put it back to stock and the car is smooth.</strong><hr></blockquote>
EXACTLY!!!!!!
wayne
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Verdad Gallardo Thread Starter
Teching In
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From: St Louis Mo
Re: Spark Plug gap??..some quick help Please Well I went back out in the garage before I saw the other post's. I gapped them at 50 and the idle does seem just a little rough,but not bad though. I will take it for a spin in the morning and see how it does. You guys said the stock gap is 39, are you refering to the stock plugs or a stock tr6?? My stock plugs that I pulled out,with 16000 mile, were all between 55 and 60. The only reason I went with the 6's instead of the 55's was because I had a very slight ping every once in a while and i thought a colder plug might help it out. I guess it's time to buy A-Tap so I can see what's really going on. Be patient with me guys this is my first computerized performance vehicle, I'm used to the old school stuff where you get out the timing light and the holley jet box, but they don't do a bit a good with this thing. Thanks for your input.
Matt
Matt
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From: USA
Re: Spark Plug gap??..some quick help Please IMHO,
your asking for trouble setting the gap larger then within .0008 of what the plug was designed at.
A TR-6 was designed for about .035, thus going .015 wider is beyond the specs and will cause the plug to fire where the outside prong is no longer straight but now angled outwards.
If you have to run .050 gap then its not a TR-6 you want. Also since TR-6 is a colder plug,you might check to see if your getting any misfire from using them.
QUOTE]Originally posted by Matt 01SS:
<strong>Well I went back out in the garage before I saw the other post's. I gapped them at 50 and the idle does seem just a little rough,but not bad though. I will take it for a spin in the morning and see how it does. You guys said the stock gap is 39, are you refering to the stock plugs or a stock tr6?? My stock plugs that I pulled out,with 16000 mile, were all between 55 and 60. The only reason I went with the 6's instead of the 55's was because I had a very slight ping every once in a while and i thought a colder plug might help it out. I guess it's time to buy A-Tap so I can see what's really going on. Be patient with me guys this is my first computerized performance vehicle, I'm used to the old school stuff where you get out the timing light and the holley jet box, but they don't do a bit a good with this thing. Thanks for your input.
Matt</strong>[/QUOTE]
your asking for trouble setting the gap larger then within .0008 of what the plug was designed at.
A TR-6 was designed for about .035, thus going .015 wider is beyond the specs and will cause the plug to fire where the outside prong is no longer straight but now angled outwards.
If you have to run .050 gap then its not a TR-6 you want. Also since TR-6 is a colder plug,you might check to see if your getting any misfire from using them.
QUOTE]Originally posted by Matt 01SS:
<strong>Well I went back out in the garage before I saw the other post's. I gapped them at 50 and the idle does seem just a little rough,but not bad though. I will take it for a spin in the morning and see how it does. You guys said the stock gap is 39, are you refering to the stock plugs or a stock tr6?? My stock plugs that I pulled out,with 16000 mile, were all between 55 and 60. The only reason I went with the 6's instead of the 55's was because I had a very slight ping every once in a while and i thought a colder plug might help it out. I guess it's time to buy A-Tap so I can see what's really going on. Be patient with me guys this is my first computerized performance vehicle, I'm used to the old school stuff where you get out the timing light and the holley jet box, but they don't do a bit a good with this thing. Thanks for your input.
Matt</strong>[/QUOTE]
Thread Starter
Teching In
Joined: Nov 2001
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From: St Louis Mo
Re: Spark Plug gap??..some quick help Please Well I had to go with the majority on this one. I pulled them back out tonight and gapped them at .039 just to be on the safe side. Some of you mentioned that the tr6's might not last as long as the 55's. How many miles do you think I should go before checking them??
Thanks again
Matt
Thanks again
Matt
TECH Senior Member
Joined: Nov 2001
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From: Mississauga, Ontario
Re: Spark Plug gap??..some quick help Please The TR6s in my 98 Formula were all done by 13k, I got a real bad high rpm hesitation that just showed up all of a sudden. Fresh TR6s cured it, even though the old ones didn't look as bad as I thought they would. The more idling you do the less mileage the TR6s will last, but I'd say changing them every 10k is about right.
