Hmmm, so I'm looking over my invoice and see they installed Brisk Racing Silver spark plugs RR14YS.
Apparently they are one step colder than stock.
Anyone ever heard of these spark plugs and are they any good?
2012 Shelby American Mustang GTS 580rwhp 485 ft/lbs Grabber Blue White Stripes
Ford Whipple, 5.0L, Tremec XL Magnum, MGW, Centerforce DYAD clutch, Boss 302 Torsen w/4:10s, 302R EPAS, Eibach Coil Overs, Fays 2 Watts Link, Dynotech DS, Shelby UCAs/LCAs, Wilwood brakes 6 piston 4 piston, Drake Bump Steer, heavy duty cooling, welded axle tubes, Interior Package, GT4 wheels, Borla Touring axlebacks, GT500 rear valence w/parking sensors, and airbag cover signed by Carroll Shelby.