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Car feels like it lacks power

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Old Nov 15, 2016 | 01:10 PM
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CorvetteGarage's Avatar
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Default Car feels like it lacks power

Randomly started feeling like it's falling on its face in 2nd & 3rd sometimes when I go WOT. As if it's pulling timing. Doesn't do it all the time, though.

No leaks, no smoke, runs & drives fine otherwise. Oil pressure & such are good too.

It's a C6Z w/cam, exhaust & tune. I pulled the NGK TR55 plugs and pics are below. The car was tuned w/these plugs over a year ago and has never given me any issues. The gap has widened out a bit, though. It's now .062. I also did a compression test and the results are below.

Compression test results (Done after car sat for a day):
2 - 240
4 - 225
6 - 225
8 - 240
1 - 210
3 - 225
5 - 225
7 - 210

To whomever deleted & banned my account I just made yesterday & posted this same post, what is the problem?



Last edited by CorvetteGarage; Nov 15, 2016 at 05:13 PM.
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Old Nov 15, 2016 | 03:17 PM
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Originally Posted by CorvetteGarage
Randomly started feeling like it's falling on its face in 2nd & 3rd sometimes when I go WOT. As if it's pulling timing. Doesn't do it all the time, though.

No leaks, no smoke, runs & drives fine otherwise. Oil pressure & such are good too.

It's a C6Z w/cam, exhaust & tune. I pulled the NGK TR55 plugs and pics are below. The car was tuned w/these plugs over a year ago and has never given me any issues. The gap has widened out a bit, though. It's now .062. I also did a compression test and the results are below.

Compression test results:
2 - 240
4 - 225
6 - 225
8 - 240
1 - 210
3 - 225
5 - 225
7 - 210

To whomever deleted & banned my account I just made yesterday & posted this same post, what is the problem?


Try going back to a stock set of plugs. I've (stupidly) run those NGK plugs before twice and both times regretted it immensely.

Believe it or not I actually got engine knock before at idle with them in the car.
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Old Nov 15, 2016 | 03:39 PM
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Originally Posted by subfloor@centurytrans
Try going back to a stock set of plugs. I've (stupidly) run those NGK plugs before twice and both times regretted it immensely.

Believe it or not I actually got engine knock before at idle with them in the car.
AC Delco 41-104, correct?
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Old Nov 15, 2016 | 03:41 PM
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Originally Posted by CorvetteGarage
AC Delco 41-104, correct?
Yes
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Old Nov 16, 2016 | 06:50 PM
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I'll agree on using the Stock plugs. Also,the gaps look pretty big.
Should be ~ .040"?? Maybe it's just me..
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Old Nov 17, 2016 | 10:14 AM
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Does it feel like a misfire? If so, it could be spark blowout due to the enlarged gap.

Many will tell you to avoid the NGK, however many of us are using them successfully.Don from Slowhawk (a really good LS tuner) uses them in his H/C C6Z builds. I commute in my car and sometimes it fouls the plugs, so I prefer just to use cheap copper plugs and change often. In your shoes, I'd throw on a new set of properly gapped TR55 and see how it does. Would be a quick/cheap test. If that doesn't fix it, I would try the delcos.
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