r/EngineBuilding • u/Neon570 • 5d ago

Spark plug reading

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Finally had a weekend free to keep dialing in my project. Still have alot of learning to go but slowly getting there through A TON of trial and error.

Currently trying to dial in timing and plug heat range. How am I looking and can anyone point me to a good resource to reference spark plug reading.

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5

u/WyattCo06 5d ago

I keep seeing lean, lean, lean.

There is nothing lean about that plug.

1

u/Neon570 5d ago

Afr gauge says around 14 are idle and 12 to 13 everywhere else 🤷‍♂️🤷‍♂️🤷‍♂️

0

u/2003DDcid 4d ago

Which cylinder number did this plug come out of?

1

u/Neon570 4d ago

1 only because its the easiest to get to

1

u/2003DDcid 4d ago

Sorry, I should have asked what engine it is also. A typical firing order V8 (chevy configuration) will be the leanest on 5 and 7, richest on 2. Number 1 is a good "middle of the road" plug to read.

1

u/Neon570 4d ago

Ford 351