Exterior Components› Body Panels and Components

XS Power

(6988) HARNESS FOR GM SI SERIES ALTERNATORS

$81.66

SKU: X008 XSP311

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Special Order
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Beginner — under 30 min

Description

The XS Power XSP311 is an alternator wiring adapter designed for GM "SI" Series Alternators manufactured between 1969 and 1988. This harness serves as the connection between an XS Power XSP310 or XSP320 Voltage Controller and your alternator. It allows for on-demand adjustment of alternator output.

Fitment

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Specifications

BrandXS Power
Part NumberX008 XSP311

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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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