GM LS Steam Vent #4 Adapter Fittings (pair)

The GM LS Steam Vent #4 Adapter Fittings (pair) by Earl's are essential crankcase ventilation components for LS-powered vehicles undergoing serious performance modifications. These fittings manage positive crankcase ventilation (PCV) routing, allowing compressed gases to escape the engine safely while maintaining proper air-to-fuel ratios. Whether you're building a street machine, race engine, or custom swap, proper steam vent plumbing prevents oil leaks, reduces backpressure, and protects internal engine seals from excessive pressure buildup.

Earl's adapter fittings are precision-engineered aluminum components designed for reliability under extreme conditions. The #4 designation refers to the ANT hose size rating, ensuring compatibility with standard LS PCV hose assemblies and catch-can systems. This pair provides dual vent routing capability, critical for high-horsepower applications where single-outlet ventilation cannot handle crankcase gases efficiently. The compact design (2.15 x 2 x 3.8 inches) allows flexible packaging in tight engine bays, while the lightweight construction (0.18 lbs per pair) minimizes parasitic weight addition.

Engine builders and LS swap enthusiasts benefit most from these fittings when integrating modern PCV systems into modified powerplants. They work seamlessly with catch-can setups, remote oil separators, and factory-style ventilation configurations. Proper installation of GM LS Steam Vent #4 Adapter Fittings ensures reliable operation across idle to redline conditions, protecting your investment in a high-performance engine build while maintaining emissions compliance and long-term durability.