Most Alternators Are Custom Built To Order. Standard Build Time Is 2-3 Weeks. If You Need An Alternator Sooner Than That, Please Contact A Sales Associate To See If Any In-Stock Options Are Available.   This is a stock replacement alternator for your 09-14 Shelby GT500. Highly recommended if you are running an aftermarket style fuel system with 2+ fuel pumps, larger heat exchanger fans and/or intercooler pumps.The 6 phase hairpin alternator offers greater idle output and efficiency than your factory 2009-2014 unitUnique rotor and stator to improve idle output. Heavy duty 12 diode twin rectifier plates Improved air flow to ensure long life in severe conditions. This unit will ship with an OEM sized pulley and this combination is suitable for stock and overdrive balancers.