spark plug gap
Thread Starter
Instructor
Joined: Jan 2017
Posts: 205
Likes: 6
spark plug gap
Hello,
I have NGK TR7ix spark plugs gapped to .032 and getting some backfire/breaking up in the high rpms. I have MSD multi spark coils which should be stronger than the originals. Do you guys think increasing the gap should fix the issue? I was thinking of gapping them to .045 this weekend
mods are v3si, cam and full bolt ons. 700hp
thanks for looking !
I have NGK TR7ix spark plugs gapped to .032 and getting some backfire/breaking up in the high rpms. I have MSD multi spark coils which should be stronger than the originals. Do you guys think increasing the gap should fix the issue? I was thinking of gapping them to .045 this weekend
mods are v3si, cam and full bolt ons. 700hp
thanks for looking !
Acct Suspended APR 2026 by request
Joined: Dec 2010
Posts: 10,367
Likes: 1,272
2020 Corvette of the Year Finalist (performance mods)
C5 of Year Winner (performance mods) 2019
if it's spark blowout then you would decrease the gap not increase it but I agree with the above, ditch the msd coils and put the oems back on and see how it does... if you still get some blowout try closing the gap to .030
Acct Suspended APR 2026 by request
Joined: Dec 2010
Posts: 10,367
Likes: 1,272
2020 Corvette of the Year Finalist (performance mods)
C5 of Year Winner (performance mods) 2019
the tr7ix is iridium and one step colder than the tr6... I used tr6's at 800rw and they did good up to that point, when I switched to e85 I started getting blowout so I went to br7ef's @ .030 and haven't had an issue since
Race Director
Joined: May 2004
Posts: 16,667
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From: Raleigh, NC
St. Jude Donor '15
Factory coils are plenty. If you're having issues, try the factory coils
I just run the regular AC Delco ZR1 plugs, I don't remember the part number. Just put them in and go. No gapping, no issues.
I just run the regular AC Delco ZR1 plugs, I don't remember the part number. Just put them in and go. No gapping, no issues.
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Race Director
Joined: Mar 2011
Posts: 13,262
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From: SW Florida
2021 C6 of the Year Finalist - Modified
I am still in the process of installing a Heartbeat SC on my 2011 GS.
I was told by a local performance shop owner and drag racer that I should get a set of TR6 plugs and gap them to .035"
I was told by a local performance shop owner and drag racer that I should get a set of TR6 plugs and gap them to .035"
Race Director
Joined: Mar 2011
Posts: 13,262
Likes: 3,151
From: SW Florida
2021 C6 of the Year Finalist - Modified
