SKU: VIB19741
UPC: 690092178666
MPN: 19741
The Reducer Coupler 4in I.D. to 3.5in I.D. x 4.5in L from VIBRANT PERFORMANCE is a precision step-down coupling designed for custom exhaust and intake manifold fabrication. This product is ideal for automotive enthusiasts looking to build turbo kits, upgrade intake runners, or adapt older exhaust components to fit modern engine configurations.
Constructed using mandrel-bent tubing principles, this reducer maintains smooth internal flow characteristics, which minimizes turbulence and velocity loss during throttle transitions. The 4-inch to 3.5-inch I.D. step-down geometry is engineered to preserve adequate runner velocity while accommodating downsized piping or component connections, ensuring optimal performance.
Engine builders, turbo installers, and street performance enthusiasts will find this coupler beneficial for custom manifold work or intake redesigns. It is also suitable for supercharger discharge plumbing, intercooler piping, or catch-can systems where diameter reduction is necessary.
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