TiAL 006391 BWVB91117-1.17 A/R BorgWarner S400 91mm Stainless Steel V-Band Turbine Housing

The TiAL 006391 (BWVB91117) is a premium investment-cast stainless steel V-band turbine housing engineered specifically for the BorgWarner S400 series with a 91mm turbine wheel at a 1.17 A/R ratio. Designed, tooled, cast, and machined in-house at TiAL Sport's facility in Owosso, MI, this housing delivers precision fitment and exceptional thermal durability for high-powered forced induction builds.

The stainless steel construction provides significant advantages over traditional cast iron housings, including reduced weight and superior corrosion resistance. The smooth investment-cast interior promotes efficient exhaust gas flow into the turbine wheel, supporting strong power output across a wide RPM range.

Key Features:

• Application: BorgWarner S400 large-frame with 91mm turbine wheel
• A/R Ratio: 1.17 — optimized for high-flow, high-horsepower applications
• Construction: Investment-cast high-strength stainless steel alloy
• Inlet/Outlet: V-band inlet and V-band outlet connections
• Inlet OD: 3.81" | Outlet OD: 4.50"
• Lighter than equivalent cast iron housings of the same A/R
• Corrosion-resistant for long service life in demanding race and street environments
• Broad A/R coverage — pairs with 91mm and 96mm large-frame S400 variants

TiAL Sport turbine housings are a benchmark in the performance turbocharging industry, trusted by professional tuners and competitive motorsport teams worldwide. The 006391 is an ideal choice for builders seeking maximum flow capability with V-band convenience on large-frame S400-based turbo systems.