Spark plug gap?
- SilverXJ
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Spark plug gap?
Should the plug gap be any different from stock for a stroker?
2000 XJ. 4.6L stroker
00+ Viper Coil Swap | CPS Timing Increase Mod | Fabricated Airbox | Dash bezel, Arduino Multigauge & RD Conceal
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Re: Spark plug gap?
i used stock, but im curious as well
- Alex22
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Re: Spark plug gap?
I'd leave it alone unless you have a high voltage coil or better than stock ignition system.
The enemy of good thing is wanting something better.
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Re: Spark plug gap?
say you had the better than stock would i open it up or close it
keepin the five alive!
- SilverXJ
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Re: Spark plug gap?
From what I read with increased compression you should close the gap up a bit.
2000 XJ. 4.6L stroker
00+ Viper Coil Swap | CPS Timing Increase Mod | Fabricated Airbox | Dash bezel, Arduino Multigauge & RD Conceal
Eat, breath, drink, sleep, Jeep, drink
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- ajmorell
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Re: Spark plug gap?
With increased voltage you open up the gap.
-Andy-
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Re: Spark plug gap?
i've got bosch platinum+2 in mine with a msd al6 and wires and the stock coil. i have mine gaped at .197 from ground to ground and centered over the tip of the plug so in a conventional plug .098ish starts and runs great.
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- darkcorp
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Re: Spark plug gap?
Hi guys!
My story.
I have viper coil mod on my 4.6 stroker (CR 9.5).
While break-in I used NGK ZFR5N (7917) spark plugs gapped to 0.035" (0.9mm). Sometimes I had missfire codes on random cylinders.
Changed 4 of them by a set of 4 spare Bosch platinum fr9hp gapped to 0.035" (0.9mm). And I've got missfire codes on all Bosch spark plugs!
Then changed them back to NGKs but gapped to 0.043" (1.1mm). Very noticeable difference in power! Engine works much smoother and responsible!
So what safest spark plug gap is possible to use on a stroker with viper coil mod? I want to try colder spark plugs with bigger gap. Maybe 0.065" or so.
My story.
I have viper coil mod on my 4.6 stroker (CR 9.5).
While break-in I used NGK ZFR5N (7917) spark plugs gapped to 0.035" (0.9mm). Sometimes I had missfire codes on random cylinders.
Changed 4 of them by a set of 4 spare Bosch platinum fr9hp gapped to 0.035" (0.9mm). And I've got missfire codes on all Bosch spark plugs!
Then changed them back to NGKs but gapped to 0.043" (1.1mm). Very noticeable difference in power! Engine works much smoother and responsible!
So what safest spark plug gap is possible to use on a stroker with viper coil mod? I want to try colder spark plugs with bigger gap. Maybe 0.065" or so.
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