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One stage colder plugs
Installed by:Pro Installer
Official sparkplug of NASCAR!
Premium Iridium plugs - 2 heat ranges colder than stock
Some would suggest Iridium is not ideal for high compression and they may be right...
Did these when I swapped out the intake manifold (easier access so was a good time).
Tell us more about your install.
Was it easy?
Any tips to share?
How is the product quality?
Autolite 5143's. Gapped at .65 with SD Coil pack and JBA wires