Originally Posted by acumenhokie
NGK 2309 (LFR7AIX) Plugs and TurboSmart 34mm BPV
So the recommended plug is
Iridium IX LFR6AIX-11
Stock num 6619
So looking at some info tying to learn..... And so the 2309s are one grade colder.
5th gen stock turbo pushes >75hp down low but is pathetic above 4k. TMIC adds about 20HP. This does not seem to warrant colder plugs.
Say above 75-100 hp from stock is a general guide to go one step cooler. What are to guidelines to go to colder plugs as a precautionary measure to keep combustion chamber temps within range, as to not pull timing to prevent detination and engine failure?
Also are the colder gapped any different than .032?