Bosch platinum spark plug C55 heat ranges
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From: Phoenix AZ & Cayucos CA
’27 AMG SL55(ordered), ‘23 EQS 580 SUV, ‘19 AMG E53 Cpe, ‘48 Willys Jeepster
Bosch platinum spark plug C55 heat ranges
From what I understand the OEM C55 Bosch spark plug is a FR8xxx (6702). But when I look at the Bosch webpage they recommend FR7xxx (6705) spark plugs, one heat range cooler.
I'm trying to understand what, if anything, changed. I drive like my grandmother lately so I suppose that the hotter plug is best, but also don't like the idea of pre-ignition issues on warm Arizona days. Has anybody had fouling issues with the cooler FR7 plugs?
I'm trying to understand what, if anything, changed. I drive like my grandmother lately so I suppose that the hotter plug is best, but also don't like the idea of pre-ignition issues on warm Arizona days. Has anybody had fouling issues with the cooler FR7 plugs?
