jimmyducati
New member
I have a '10 SHO and replaced the plugs last month... Gapps were crazy from .025 to .045, leading me to think they don't do anything with gaps when the engine is built.. a tad disappointing when buying a $45k car if you ask me 
I replaced them with the recommended NGK plugs, properly gaped and it runs smoothly now. Also wrapped and shielded that knock sensor wire that runs along the drivers side front head. It gets chaffed and can cause the timing to retard randomly.
A suggestion, on cars with some mileage on them (35k+) I would have some of the rubber boots that hold the spring that makes contact between the spark plug and coil on hand. 2 of mine were "fused" to the spark plug and had to be fished out with needle nose pliers, ruining them. They are only a few bucks a piece.

I replaced them with the recommended NGK plugs, properly gaped and it runs smoothly now. Also wrapped and shielded that knock sensor wire that runs along the drivers side front head. It gets chaffed and can cause the timing to retard randomly.
A suggestion, on cars with some mileage on them (35k+) I would have some of the rubber boots that hold the spring that makes contact between the spark plug and coil on hand. 2 of mine were "fused" to the spark plug and had to be fished out with needle nose pliers, ruining them. They are only a few bucks a piece.