spark plug preferences?
Le Mans Master
Joined: Oct 2000
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From: Sausalito CA
Listen to Richie.
As for power......there isn't a gain.
However, indexing you give you fuel igniting efficiency.
I personally like to change iridium or long life plugs not at 100K miles as many OEM recommend, but at 50K. I just like to not "play" with aluminum sparks plug holes that often. Plus at 100K many plugs are stubborn in their removal.
As for power......there isn't a gain.
However, indexing you give you fuel igniting efficiency.
I personally like to change iridium or long life plugs not at 100K miles as many OEM recommend, but at 50K. I just like to not "play" with aluminum sparks plug holes that often. Plus at 100K many plugs are stubborn in their removal.
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
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So.... What does the ZR1 use as a spark plug? Isn't that Iridium? ZR1 .040 AC 41-104
http://forums.corvetteforum.com/1574050358-post6.html
Elmer
Last edited by eboggs_jkvl; Dec 21, 2010 at 01:05 PM.
Safety Car
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From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
In a word? No. You should not close the gap on ANY plug more than .010. I think the TR55s are gapped at .055 and closing them down to .035 is .020 and not cool. You should have used the TR6. It starts out at .039 and closing it down to .035 is no problem.
I think the old rule was .010 less gap for every 50 RWHP added. Also, FI needs the smaller gap so you don't blow out the spark under high boost. Honestly? I switched to the ZR1 stock plug. It seems to be perfect for my situation. ~500 RWHP and a .040 gapped Iridium.
Elmer
I think the old rule was .010 less gap for every 50 RWHP added. Also, FI needs the smaller gap so you don't blow out the spark under high boost. Honestly? I switched to the ZR1 stock plug. It seems to be perfect for my situation. ~500 RWHP and a .040 gapped Iridium.
Elmer
Changing the gap on a TR55 to .040" results in the ground electrode bent too far and not presenting itself as parallel to the center electrode.
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I've posted a number of times that NGK admitted their website incorrectly showed the TR55 for the 2005 Corvette. I wrote them an email and they came back saying the TR5 gapped at .040" is the correct plug for the Corvette.
Changing the gap on a TR55 to .040" results in the ground electrode bent too far and not presenting itself as parallel to the center electrode.
Changing the gap on a TR55 to .040" results in the ground electrode bent too far and not presenting itself as parallel to the center electrode.
Elmer
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So.... What does the ZR1 use as a spark plug? Isn't that Iridium? ZR1 .040 AC 41-104
http://forums.corvetteforum.com/1574050358-post6.html
Elmer
http://forums.corvetteforum.com/1574050358-post6.html
Elmer
Team Owner
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From: Long Island New York
I should have said high boost applications. The ZR1 uses the same plugs as the LS7. I have heard of people switching out to NGK's for higher then stock boost levels, but I personally do not think there is anything wrong with the stock Iridiums for FI applications. Many shops have posted info about not being the optimum plugs for FI, but I am not sure if there is evidence to support it or not, other then wanting to change the heat range.
