This SBC-3.9L-390XP alternator generates a maximum of 390 Amps at normal driving speeds and produces 220 Amps at idle. The XP series of SBC alternators are assembled using DENSO components and produce the highest idle output. They feature larger housing while still retaining OEM fitment without any modification required. They run cooler and are virtually indestructible.
This alternator comes with an unprecedented full two year warranty.