Ultra Series GM 10SI Alternator w/ Serpentine Pulley, 140 AMP, Black Finish

GM 10SI High-Output 140 Amp Alternator – Black

The Ultimate "One-Wire" Charging Solution for GM & Custom Builds

Upgrade your charging system with the legendary GM 10SI Series High-Output Alternator. Combining classic 1970s-80s fitment with modern 140-amp internals, this unit is the perfect solution for muscle cars, street rods, and trucks that need extra "juice" for electric fans, high-end audio, and modern electronics.

Optimized for Performance

• Massive 140 Amp Output: Offers a significant boost over stock 37-amp or 63-amp units, ensuring your battery stays charged even with high-draw accessories.
• Superior Low-Idle Charging: Featuring an ultra-low cut-in voltage regulator, this alternator starts charging almost immediately at low RPMs—no more flickering lights at the stoplight.
• Simplified 1-Wire Hookup: Designed for a clean, hassle-free installation. Eliminate the "rats nest" of factory wiring by running a single cable directly to your battery.
• Heavy-Duty Internal Construction: Built with high-density copper windings and premium steel to maximize heat dissipation and electrical efficiency.

Premium Sleek Finish

• Black Housing: The high-luster polished finish provides a mirror-like look that complements any chrome or painted engine bay.
• Complete Pulley & Fan Kit: Comes pre-installed with a Black Serpentine Pulley and a high-flow Black Steel Fan for maximum cooling and belt traction.
• Neoprene-Sealed Bearings: We use only the highest-quality neoprene seals to keep grease in and dirt out, ensuring a long, quiet service life.