M156 Spark Plugs - Interesting
07-30-2009, 08:12 PM
#1
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2007 E63 w/P30 and Eurotech CF Diffuser
M156 Spark Plugs - Interesting
From NGK's web site from 2006. The reasons for the design are interesting.
NGK’s ILZKAR7A10 iridium spark plug has been chosen for OE fitment to the 365kW, 6.3-litre V8 power unit developed by AMG for use in high-performance derivatives of Mercedes models. In this case, the main requirement was for the slimmest possible spark plug with sufficient performance, in order to leave as much space as possible in the cylinder heads for both valves and coolant passages. To satisfy this need, NGK developed this new plug with a 12mm thread, but a 14mm hexagon and a slimmer ceramic insulator. The length remains 26.5mm.
07-30-2009, 10:37 PM
#2
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Thought you were going to show us your old plugs. :)
12,000+ rpm Asian motorcycle manufacturers have utilized the small thread/long reach design for decades. Higher specific output engines have yet to be made available for general road going applications.
It’s likely prudent one disregard MB’s 100,000 mile replacement recommendation if he intends to keep it a while or enjoys exploiting all of the OE performance for which he paid. Mine squeaked something fierce upon removal at ~45,000. No damage, but installing a Heli-Coil thread repair insert is no picnic.
Curious that AMG felt compelled to source many of their plug fitments from NGK instead of a German supplier. Probably wise, as more than a few Bosch trinkets have not always proven to be dead nuts reliable.
https://mbworld.org/forums/w211-amg/...g-upgrade.html
12,000+ rpm Asian motorcycle manufacturers have utilized the small thread/long reach design for decades. Higher specific output engines have yet to be made available for general road going applications.
It’s likely prudent one disregard MB’s 100,000 mile replacement recommendation if he intends to keep it a while or enjoys exploiting all of the OE performance for which he paid. Mine squeaked something fierce upon removal at ~45,000. No damage, but installing a Heli-Coil thread repair insert is no picnic.
Curious that AMG felt compelled to source many of their plug fitments from NGK instead of a German supplier. Probably wise, as more than a few Bosch trinkets have not always proven to be dead nuts reliable.
https://mbworld.org/forums/w211-amg/...g-upgrade.html
