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Spark Plug Gapping

binga85

By binga85,
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binga85 Community Regular

binga85

Posted
Posted (edited)

I'm sure this has been covered, though I'm on my phone and I'm restricted searching.

anyway.....

changed my plugs yesterday to the NGK iridium bkr7ex and it's missing under WOT 6000rpm +

Any advise as to what i should gap the plugs to??

currently doing around 320awkw at 16psi with 1000cc injectors

thanks

Edited by binga85
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https://www.sau.com.au/forums/topic/393489-spark-plug-gapping/
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  • 2 months later...
GTRNUR Grand Master

GTRNUR

Posted
Posted

Your air-fuel ratio's will play a big part in your success or failure here. If your fuel ratio's are dipping deep into and past the 11's, then 0.8 won't be enough. Aim for 12:1. Transitions can be tricky with big injectors too. Really for that power you only need 550cc's.

Plug gapping to fix this is really just a bandaid to cover up the fact the tune is too rich. 6 heat range is fine for 320kw too, there is no benefit in going to 7's or super cold race plugs. In fact a hotter plug will foul less.

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