i know this thread is 2 yrs old, but my question to the more knowledgeable members, back in the day, we would close the gap on the plugs. so, since the gap is .043, would closing the gap to .030 be of any benefit or are modern cars that advanced that it isn't needed. on my stinger gt, i closed the gaps from the factory .060 (?) to .032 and the difference is readily felt. but, that car is also a twin turbo. thanks to everybody for reading this. let the comments begin!!!!
I believe that closing the gap on a spark plug in a high performance car that is governed by fuel and timing maps is not a necessarily a good thing. The engineers spec. a certain type of plug, platinum, iridium, etc... and a certain gap so that they can accurately time the firing of the spark plug. If you decrease the gap, you essentially advance the spark timing a bit because you've lowered the resistance by closing the air gap. If you change the metal type used in the spark plug, you either lower or increase the resistance that spark plug offers causing a slight change in timing. In the old days it didn't much matter and today we have knock sensors that will retard the timing to protect the engine, the same as if we were running a low octane fuel. You probably won't hurt anything, but it likely won't help either.