E3 Spark Plugs for automotive and powersports applications have a unique multi-leg ground electrode that is pre-gapped at our factory to meet the O.E. requirements for the vehicles they are listed to fit. No further gapping is required.
E3 Lawn & Garden spark plugs are gapped at the factory, but may require some adjustment to meet your O.E. engine requirements.
Racing applications and modified engines change the heat range requirement of the OEM plug, and sometimes even the physical dimensions. Performance modifications often involve changes to the combustion area to include the engine’s cylinder, pistons, head or valves. E3’s racing spark plugs’ gap cannot be changed. Check with your engine builder before installing spark plugs.