Will diff plug gap affect tune?
Thread Starter
Melting Slicks
Joined: Nov 2011
Posts: 3,161
Likes: 257
From: Virginia
Will diff plug gap affect tune?
Had my car tuned with ngk tr55's gapped at .050 I believe not positive about that. I plan on changing plugs soon and was wondering if I increased plug gap to .060 would it negitavely affect the tune. Still plan on going with the tr55's.
Race Director
Joined: Jan 2008
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From: oregon
factory gap was .4x
https://www.corvetteforum.com/forums...50-60-a-2.html
however a lot of guys have ran .55 on the tr55 without issue. make sure you only run the highest octane available. as .55 is a large gap
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plug gap varies depending on which plug you use, so what might be optimal for factory plugs may not be optimal for everything else
Thread Starter
Melting Slicks
Joined: Nov 2011
Posts: 3,161
Likes: 257
From: Virginia
factory gap was .4x
https://www.corvetteforum.com/forums...50-60-a-2.html
however a lot of guys have ran .55 on the tr55 without issue. make sure you only run the highest octane available. as .55 is a large gap
https://www.corvetteforum.com/forums...50-60-a-2.html
however a lot of guys have ran .55 on the tr55 without issue. make sure you only run the highest octane available. as .55 is a large gap
Race Director
Joined: Jan 2008
Posts: 16,027
Likes: 169
From: oregon
in fact i usually err on the smaller side of gaps. there is only a hp or two difference but smaller gaps mean you don't have to worry about detonation caused by the plugs
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GM originally reccdm. a plug gap of .060 However in the last few years they now reccmd the plugs to be gapped at .040---------Reducing the gap will have no affect on either HP or TQ----- They found out that the larger gaps had a tendency to cause misfires---
and even overheat the coils------The newly reeccmd gap of .040 will eliminate any coil overheating and any chance of a misfire----The eng when cold will run much smoother and all thru the P/T RPM's it will run much better----
A TR5 is pregapped at .040 but they are hard to find Easier find is the TR55 pregapped at .060 so simply re gap them at .040
and even overheat the coils------The newly reeccmd gap of .040 will eliminate any coil overheating and any chance of a misfire----The eng when cold will run much smoother and all thru the P/T RPM's it will run much better----
A TR5 is pregapped at .040 but they are hard to find Easier find is the TR55 pregapped at .060 so simply re gap them at .040