How (and why) do spark plugs need to be tightened for best performance?
A.It is very important to properly tighten spark plugs during installation. Too little torque can cause the spark plug to leak combustion gases and poor heat transfer of the plug seat to the cylinder head. Over-torque can damage both the spark plug and the threads in the engine head. Both can cause extensive engine damages. Your Autolite® Master Catalog lists the proper torque specs for various spark plug sizes. If not available, use this guide.
