G-tech Motorsports BMW B58 Pre-OPF 5-Inch Stainless Steel Downpipe

Upgrade your BMW B58 engine with the G-tech Motorsports 5-inch stainless steel downpipe and remove the factory restriction that limits performance. Designed for Pre-OPF models, this high-flow downpipe improves turbo spool, throttle response, and delivers an aggressive exhaust tone for road and track. Key Features & Benefits: Oversized 5-inch diameter for maximum exhaust flow Premium T304 stainless steel for durability and corrosion resistance Mandrel-bent tubing for smooth airflow and faster turbo response Integrated heat shield to lower engine bay temps Motorsport-grade TIG welding for strength under high boost Deep, aggressive exhaust tone compared to OEM pipes Brushed stainless finish for a performance look Vehicle Compatibility / Fitment: Fits BMW B58 Pre-OPF models: M140i (F20/F21) M240i (F22/F23) 340i (F30/F31/F34) 440i (F32/F33/F36) 540i (G30 – Pre-OPF only) 740i (G11/G12 – Pre-OPF only) X3 B58 (G01 – Pre-OPF only) Technical Specifications: Diameter: 5-inch inlet tapering to OEM connection Material: T304 stainless steel Finish: Brushed stainless Construction: TIG welded Heat Shield: Integrated Installation Information: Tools required: standard exhaust tools, torque wrench Install time: 1–2 hours Professional fitting recommended for best results Performance Gains / Why It’s Needed: The stock downpipe restricts exhaust flow. G-tech’s 5-inch design delivers: Stock cars: +25–30bhp and sharper throttle response Stage 2: up to +120bhp with ECU remap Hybrid / big turbo: supports 700hp+ builds Lower exhaust gas temps and quicker spool throughout the rev range What’s Included: 1x 5-inch stainless downpipe Integrated heat shield Full installation hardware Warranty & Guarantee: Comes with manufacturer warranty and return policy on unused products. SEO Extra Details: Relevant terms: BMW B58 downpipe, stainless downpipe upgrade, 5-inch performance exhaust, Stage 2 B58 tuning. See also intercoolers and turbo upgrades for BMW performance builds. FAQs: Q: Why choose 5-inch over 4.5-inch? A: More exhaust flow, ideal for tuned and big turbo setups. Q: Is this for Post-OPF engines? A: No, only Pre-OPF B58 models. Q: Do I need a remap? A: Gains are best with Stage 2 tuning, but it also works on stock software. Q: Will it change the exhaust sound? A: Yes, expect a deeper and more aggressive tone.