Doug's Headers D6652 Long Tube 4-Tube Exhaust Header 1-3/4" Primary 3" Collector

The Doug's Headers D6652 is a full-length, long tube 4-into-1 exhaust header engineered for maximum performance gains across the entire RPM range. Built with the precision and craftsmanship Doug's Headers has been known for since 1958, this header is designed for Coyote 5.0L engine swap applications and delivers the kind of power increase that only a properly tuned long tube header can provide.

Key Features:

• 3/8" thick machined flanges — Precision machined to prevent warping and ensure a leak-free seal
• CNC mandrel bent tubes — Maintains consistent tube diameter throughout every bend for accurate fitment and unrestricted exhaust flow
• 1-3/4" primary tubes with 3" collector — Optimally sized to scavenge exhaust gases efficiently and reduce pumping losses
• Precision formed long transition collectors — Long tube design reduces backpressure and builds higher RPM horsepower and torque
• Heavy-duty 16-gauge steel tubing — Built for long-lasting durability under demanding conditions
• Pre-polished tubes — Tubes are pre-polished to remove surface scratches before coating is applied

What's Included:

• Sold as a pair
• All necessary mounting hardware
• Collector reducers or connector pipes
• Premium extra-thick gaskets (rated to 1,100°F and 3,700 psig)
• Detailed installation instruction sheet

Available Finishes:

• Metallic Ceramic Thermal Barrier Coating (MCTBC) — Vibratory-polished for a high-luster aluminum appearance; 60% more corrosion resistant than an unpolished surface and creates a thermal barrier that reduces under-hood temperatures
• Hi-Temp Black Coating — Durable high-temperature black finish
• Raw Steel (Natural) — Uncoated for custom finishing
• 304 Stainless Steel — Premium corrosion-resistant construction

Every Doug's header is individually tuned with the correct tube size and length to efficiently evacuate exhaust gases from each cylinder, reducing pumping losses for dramatic gains in horsepower and torque. Headers are developed and fitment-verified directly on the vehicles they are intended for, and re-checked multiple times throughout the design and manufacturing process.