Early GM High Output Alternator – Internal Regulator
Natural Aluminum or Chrome Finish
Upgrade your classic GM vehicle or custom build with our most popular high output replacement alternator. Available in natural aluminum or chrome, this internally regulated alternator delivers exceptional performance, especially at idle.
🔧 Key Features:
- Direct Replacement for GM 10SI & 12SI alternators (1963–1983)
- High Output at Idle – Designed to produce more amps at low RPM than stock units at high RPM
- Simple 1-Wire Installation – Connect the battery cable to the rear and you're done
🚗 Perfect for:
- Street rods
- Project cars
- Classic GM vehicles
- Replacing alternators or generators (internal/external regulation)
⚙️ Installation Benefits:
- Self-exciting: Just start the engine, give it a slight rev, and it begins charging automatically
- Optional W290 wiring harness enables dash light functionality
- Available in natural aluminum or chrome finish to match your build
Looking for even more power?
👉 Check out our Mega Amp Alternator – a direct-fit, higher-amperage upgrade.