Haltech Alternator Pigtail - LS Harness Alternator Adapter - Large - Hitachi/Mitsu Alternators

Overview

The Haltech Alternator Pigtail HT-040091 bridges the gap between your LS harness and Hitachi, Mando, or Mitsubishi alternators with a proper OEM-grade connection. Essential for JDM alternator swaps, hybrid builds, or when converting LS engines with non-GM charging systems. No more bodged connections or voltage drop issues compromising your charging circuit.

Technical Specifications

• Part Number: HT-040091
• Connector Type: Large Yazaki 2-pin to GM Delco/Bosch style
• Application: Hitachi, Mando, Mitsubishi alternators
• Wire Gauge: Heavy duty automotive grade
• Dimensions: 5.4" length, compact fitment

Why You Need This

LS swaps into JDM chassis often retain the original alternator for clearance or cost reasons, but the wiring doesn't match. The large Yazaki connector on Hitachi and Mitsubishi alternators won't mate with GM LS harnesses, leaving builders with unreliable splice joints or incorrect connections. Poor alternator connections cause voltage drop, ECU instability, and charging issues that can strand you trackside.

This adapter eliminates the guesswork. We see it constantly on S-chassis SR20 to LS conversions, RX-7 LS swaps retaining the stock alternator for clearance around the turbo, and Supra builds where the original alternator placement works better than relocating to a GM unit. The heavy-duty construction handles the full charging circuit current without voltage loss, while the OEM-style connectors ensure a weatherproof seal that won't corrode or work loose.

ECU & System Compatibility

Works with any LS harness setup, whether you're running a Haltech Elite 550, Elite 1000, or Nexus R5. The alternator circuit is independent of ECU choice, but proper charging system voltage is critical for ECU stability and sensor accuracy. Compatible with all Haltech engine management systems that require stable 12-14V supply.

What's in the Box

• Haltech HT-040091 alternator pigtail adapter
• Large Yazaki 2-pin connector (alternator side)
• GM Delco/Bosch style connector (harness side)
• Heavy duty connecting leads

Complete Your Build

Most customers fitting LS engines with JDM alternators also need proper engine harness solutions and ECU mounting hardware. Our technical team can recommend the complete wiring package for your specific swap, whether it's a stand-alone setup or integrated with factory systems. With UK stock and same-day despatch, we'll have your charging system sorted without the usual import delays. Contact our pre-sales team for application-specific advice on alternator compatibility and harness requirements.