Holley's premium alternator is built to handle 30% higher RPM than a conventional unit, with a sculpted all-aluminum housing designed for performance engines that get pushed hard on the street, strip, or auto-cross.
Specifications:
- Output: 150 Amps
- Alternator Style: O.E. or 1-wire
- Engine Fitment: GM Gen III/IV (LS)
- Material: Aluminum
- Finish: Black
- Pulley: Serpentine, 6-rib, Internal Fan
- Voltage Regulation: Internal
- Part Number: 197-303
Fits all Holley accessory brackets, 4th generation F-body, most 1998-2004 GM trucks, and other compatible applications. Uses weatherproof plug/pigtail P/N 197-400 (sold separately); matching black or polished pulley covers are available as P/N 97-187 and 97-188.
FAQ
What output does this alternator provide?
150 amps.
What engines does it fit?
GM Gen III/IV (LS) engines with all Holley accessory brackets, plus most 4th-gen F-body and 1998-2004 GM trucks.
What finish is available?
Black, with matching black or polished pulley covers sold separately.
Does it need a special connector?
Yes, it uses weatherproof plug/pigtail P/N 197-400, sold separately.

