Spark plug gap
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From: Out Where the Buses Don't Run, Eglin AFB/ Niceville FL
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Spark plug gap
I'm getting ready to install the AC 41-104 plugs in my 2006 supercharged LS2 to hopefully get rid of the random "Service Charging System" message. What is the recommended plug gap for these in this application? I currently have NGK's installed. Thanks.
Will work for HPDE time.
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From: Orlando FL
I'd run a little less gap on an FI car. Depending on how much boost, between .032 and .038, so you don't end up blowing out the spark. Is this a TR6 equivalent? (One heat range colder)
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Will work for HPDE time.
Joined: May 1999
Posts: 2,560
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From: Orlando FL
Well, there's a few reasons. He isn't driving a ZR1. He has a LS2 car with an aftermarket centrifugal blower, which may or may not be running double-digit boost #s. Factory NA gap is .040. I experienced spark blowout at .035 and 12#s of boost in my turbo LS2 with TR6s.
Elmer, I see you have a FI car as well. If it's working for you, it might work for him as well.
Every car's different.
Elmer, I see you have a FI car as well. If it's working for you, it might work for him as well.
Every car's different.
Last edited by TNTC4VETTE; Nov 6, 2011 at 05:53 PM.
Thread Starter
Race Director
Joined: Jul 2000
Posts: 16,483
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From: Out Where the Buses Don't Run, Eglin AFB/ Niceville FL
2025 C8 Z06/7/E-Ray of the Year Finalist - Unmodified
2022 Corvette of the Year Finalist -- Modified
2021 C6 of the Year Winner - Modified
2020 C7 of the Year Finalist -- Modified
2020 C6 of the Year Finalist - Modified
Thanks guys. I'm running on the conservative side at 7-8psi boost max. The NGK's were set to .040 so I was pretty sure these would be the same but I wanted to verify with some of you that have been running FI longer.
