I just put the NGK V-power plugs in my car. I have heard that the stock motorcraft plugs will run better. But some people have told me I would need a little hotter burning plug because im running the o/r prochamber now.
the thread size on the plugs is a tad different, a buddy of mine has a piston hit the plug and it shot out of the coil pack so i took mine out and installed factory motorcraft plugs