A friend swears by NKG (not sure of the equivalent, found a list of over 20 numbers!), I tried some E plugs (green) at the small motor place that run a lot cleaner and the Kohler 27 seems to start better and consistently; the Champions appear more fouled after 20 hours than the E ones. Any reasons I should not use the E type? They have a V notch and are supposed to be more "efficient". I always keep some spare Champions on board, but if anyone can recommend a better type, please elucidate! Trying to squeeze all the performance of my glorified lawnmower engine. The mower shop guy shakes his head and says no difference in spark plug, oil, etc. but non-engineer me knows better. I have pretty much confirmed the spark plug gap at .030" for the 27, anyone say other?

I just wanted to add that my vintage (2004) Kohler 27 runs fine; I use synthetic Mobil 1 oil and grease in the shaft housing, I believe they both improve performance. I change plugs twice a season, because I do run a lot before during scouting time and many hours during the regular season and I've compiled a bunch of hours during teal. The Champions are fine and cheap but I would not mind spending a couple of bucks more...after hearing some horror stories on the Fram oil filters last year, I treated my motor to a highly rated Bosch filter. If anyone wants to part with their shiny Q muffler I will gladly accept it!