4-1 Merge Collector 2.375in Inlet ID 4in Out

The 4-1 Merge Collector 2.375in Inlet ID 4in Out from Vibrant Performance is a high-flow exhaust manifold designed for engine builders and performance enthusiasts seeking improved scavenging and power delivery. This four-into-one collector merges individual cylinder exhaust runners into a single outlet, optimizing exhaust gas evacuation across the RPM band. Whether you're building a street engine, weekend track car, or naturally aspirated performance platform, this collector serves as the foundation of an efficient exhaust system.

Engineered with a 2.375-inch inlet diameter and 4-inch outlet, this merge collector balances runner convergence to minimize turbulence while maximizing flow velocity at the collector exit. The stepped design manages flow transitions smoothly, preventing the exhaust reversion that can rob power in poorly designed systems. Vibrant Performance's manufacturing standards ensure smooth internal passages and consistent welds that reduce flow restrictions.

Technicians and fabricators working with four-cylinder, V6, or modular engine swaps benefit from this collector's universal application. Its lightweight design of just 3.16 pounds allows for easy integration into custom exhaust fabrication projects without adding excessive weight. The compact dimensions of 6.75 x 6.35 x 12.25 inches facilitate flexible downpipe routing in tight engine bays common to retrofit and swap applications.