Ngk spark gap

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81camaro
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Ngk spark gap

Post by 81camaro » Fri Oct 13, 2017 5:30 am

Thanks to some recommendations I bought ngk r5673-8 for my combination. I spoke with Jason Norwood of ngk and he recommended this plug also. My question is he said to leave the gap at what the plug comes out of the box. I’ve checked a few and this gap is a tight 20 at best. I was running 43 with my previous ac delco plugs. What’s everyone else running for gap??

Geoff2
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Re: Ngk spark gap

Post by Geoff2 » Fri Oct 13, 2017 5:38 am

If it is HEI, GM specified 0.060" gap. If you are using good quality leads [ which is anything but graphite ], you will be ok.

81camaro
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Re: Ngk spark gap

Post by 81camaro » Fri Oct 13, 2017 6:42 am

Ignition is digital msd 6Al-2 with built in 2 step. Blaster 2 coil and msd wires.

FastBuick
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Re: Ngk spark gap

Post by FastBuick » Sun Oct 15, 2017 6:07 pm

Not sure what your combo is, but I run .020" gap in my engine with NGK plugs.
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peejay
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Re: Ngk spark gap

Post by peejay » Sun Oct 15, 2017 6:09 pm

The reason you run the NGK racing plugs how they are gapped is the porcelain gets so "short" that they can flash over as a surface discharge rather than across the gap, if the gap is too wide.

Some of those plugs need to be gapped as tight as .010".

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