How important is proper spark plug installation torque?
Torque is the most critical part of installation. A spark plug can only transfer heat effectively when it is fully seated on the cylinder head. Under-torqued spark plugs will not seal and transfer heat effectively. Over-torquing can distort a spark plugs internal seals and cause poor heat transfer. aplug with poor heat transfer will allowcylinder temperatures to rise dramatically – eventually leading to detonation and plug or engine damage. To ensure proper torque when installing spark plugs, clean the threads in the head and on the plug, use anti-seize sparingly, and don’t guess – use a torque wrench.
