SBC IMCA Headers 1-5/8

The SBC IMCA Headers 1-5/8 by SCHOENFELD represent a purpose-built exhaust solution for small-block Chevrolet engines competing in IMCA racing and high-performance street applications. These headers are engineered specifically for drivers who demand maximum scavenging efficiency and responsive throttle characteristics without sacrificing durability or ease of installation. Built to IMCA specifications, they serve as the foundation for any serious SBC power build seeking improved exhaust flow and engine breathing.

Constructed with 1-5/8-inch primary tube diameter, these headers optimize exhaust gas velocity and scavenging across a broad RPM band, which is critical for IMCA-class engines where power curves must remain predictable and repeatable. The 1-5/8-inch sizing balances mid-range torque with high-RPM efficiency—larger than street headers but precisely calibrated for naturally aspirated small-block Chevrolet displacement and compression ratios typical in IMCA competition. SCHOENFELD's proven tube design and collector geometry eliminate reversion and promote cleaner exhaust evacuation, translating directly to improved cylinder filling and more horsepower at the wheels. The headers are finished to withstand thermal cycling and corrosive exhaust environments, ensuring longevity even in full-race duty.

IMCA racers, weekend bracket warriors, and small-block Chevrolet hot-rodders benefit most from this design, particularly those running carbureted or naturally aspirated configurations where every fraction of a percent in efficiency counts. Installation requires proper fitment verification with your specific engine bay and exhaust system; confirm clearance with steering components, suspension, and fuel system routing before ordering. These headers are engineered to bolt directly to factory SBC flanges and integrate seamlessly with aftermarket intake manifolds and carburetor combinations. For optimal results, pair with a matching collector system and quality gaskets to ensure leak-free sealing and repeatable performance gains on the dyno or track.