Moin! Can someone introduce me to the heat values of spark plugs again n bitsl? Let’s take as an example the C20XE, which has as a serial motor candles of e.g. Bosch with the identification FR8LDC (no 100% warranty on the identification, but was believe something with 8 ) When and why then use “colder” candles (e.g. one with a 7 instead of a 8 ) and how are the colder ones? I only know this from reading with more powerful engines (e.g. Mantzel PowerBox on the X14XE [believe Zero sch This is why my thought was that if you install a “sharp” camshaft, the engine gets more air through longer opening times and a larger valve stroke, which could possibly lead to a slightly leaner mixture (believing to have read that a minimally lean mixture is optimal for maximum power, than NOT Lambda=1 ?!), which in turn means that the combustion temperatures rise slightly (please correct me if I am wrong). Are other candles used for this reason, because they may have more heat off (even if the term “colder” candles would be a bit misleading) or do I think that I’m just full of wood? I hope you can make me a little smarter. Thx so far