Performance Headers for 1977–1979 Ford F-250 4WD – 351M / 400M V8

Upgrade your 1977-1979 Ford F-250 (4WD) with Flashark Exhaust Headers designed for 351M and 400M engines (5.8L/6.6L). These headers improve exhaust flow, reduce back pressure, and boost horsepower for optimal engine performance. Fitment: 1977-1979 Ford F-250 – 351M/400M 5.8L/6.6L 4WD Note: Also fits other 1977–1979 Ford 4WD models like F-100, F-150, F-350, and Bronco. See full compatibility here . Details: Standard Uncoated Headers: 1-5/8 in. Tube Dia: FULL-LENGTH Design Primary Tube Diameter (in):1.625 Tubes Tube Diameter:1-5/8 in Reducer Outlet Size: 2-1/2 In. Collector Diameter: 3 In. Collector Size: 3 In. Specifications: Brand Name: FLASHARK Certificate: ISO9001:2000 Application: Automobile Exhaust Header Surface: Mirror Polish Model: EH28225 Material: Stainless Steel Our black Exhaust Header features a high-quality black coating over durable stainless steel, specifically designed for 351M and 400M engines. This extra layer enhances the appearance while protecting the header from harsh driving conditions, ensuring long-lasting performance and reliability. Features: Tuned-length primary tubes for maximum exhaust scavenging and velocity Mandrel-bent tubing for smooth exhaust flow Long transition collector for decreased back pressure 5/16 machined flanges for a perfect seal Industry™s best welds for durability Designed for optimal performance All necessary hardware included for a complete installation Exhaust Headers vs. Manifold: Why Headers Are the Best Upgrade for Your 351M Engine The key difference between exhaust headers and manifolds is in both material and performance. Exhaust headers, made from lightweight, high-quality steel, are designed to optimize exhaust flow. Unlike thick iron manifolds, headers are longer and have individual tubes for each cylinder, which helps eliminate back pressure. This results in increased horsepower and improved efficiency, especially for 351M/400M engines. Upgrading to Flashark Exhaust Headers will enhance engine performance and exhaust sound for your Ford Bronco or F-Series with a 351M/400M engine. Whether for daily driving or off-road adventures, these headers are engineered for maximum power with an easy, direct bolt-on installation—no modifications needed. Why Choose Our Natural Stainless Steel Headers Over Black-Coated Alternatives? While some competitors offer black-coated headers for a "stealth" look, our untreated stainless steel headers provide superior durability and long-term performance without compromises. No Peeling or Fading – Black coatings often chip, flake, or discolor under extreme heat, leaving a patchy, worn appearance. Our bare stainless steel maintains its integrity for years, resisting corrosion and wear. Better Heat Dissipation – Coatings can trap heat, reducing efficiency. Unpainted stainless steel allows optimal thermal transfer, helping your engine run cooler. Zero Maintenance – Unlike coated headers that require touch-ups, our stainless steel finish stays clean with minimal care—no worries about scratched paint or rust spots. Proven Material Quality – High-grade 304 stainless steel naturally resists oxidation, so it won’t degrade like cheap painted alternatives. FAQ Q1: What are the primary performance benefits of installing Flashark long tube headers on a 1977-1979 Ford F-250 4WD with a 351M or 400M V8? A1: Flashark long tube headers replace your restrictive factory cast-iron manifolds with individual tuned-length primary tubes. This design eliminates performance-robbing backpressure and maximizes exhaust scavenging, unlocking significant gains in both horsepower and low-end torque. It is the ultimate modification to improve throttle response and raw towing power for your classic 77-79 Ford truck. Q2: Which Ford truck models and engine sizes are compatible with these performance headers? A2: These Flashark performance exhaust headers are a precision fit for 1977, 1978, and 1979 Ford F-100, F-150, F-250, F-350 4WD pickup trucks, as well as 1978-1979 Ford Bronco 4WD models. They are exclusively engineered for Ford M-block V8 engines, specifically the 351M (5.8L) and 400M (6.6L) configurations. Q3: Will these long tube headers fit 2WD Ford trucks or alternative engines like the 351W or 460? A3: No, these headers are specifically designed and clearance-tested for 4WD (Four-Wheel Drive) models to cleanly clear the front driveshaft and transfer case setup. They will not fit 2WD models or other engine families such as the Small Block Ford 351 Windsor (351W), 302, or Big Block Ford 460 engines. Q4: What are the exact tube and collector dimensions of the Flashark 351M/400M headers? A4: Engineered for optimal exhaust gas velocity and volumetric flow, these headers feature a 1-5/8 inch (1.625") primary tube diameter. They flow into a 3-inch collector and include a 2-1/2 inch reducer outlet size to allow for a seamless connection to your aftermarket or custom dual exhaust system. Q5: Should I choose the Natural Stainless Steel or the Black Coated variant for my Ford 400 V8 headers? A5: Both options are constructed from premium, durable stainless steel. The natural mirror-polished stainless steel provides a show-quality classic look that natively resists corrosion. The high-quality black coating adds an extra layer of thermal protection and a stealth look, perfectly matching rugged off-road builds while shielding the header from harsh driving conditions. Q6: Is this 1977-1979 Ford F-250 exhaust header set a direct bolt-on installation? A6: Yes! Flashark performance headers are engineered as a direct replacement solution that matches original factory specifications, eliminating the need for cutting, welding, or custom fabrications. The kit comes complete with a pair of long-tube headers, reducer collectors, high-temperature gaskets, and all necessary mounting hardware for a straightforward bolt-on upgrade. Q7: How do mandrel-bent tubes on Flashark headers improve exhaust flow over stock 351M manifolds? A7: Traditional cast-iron exhaust manifolds force exhaust gases through sharp corners and restrictive chambers, creating severe pressure buildup. Flashark headers utilize mandrel-bent tubing which maintains a constant inner pipe diameter throughout every bend. This smooth, unobstructed path accelerates exhaust flow velocity, letting your 351M or 400M engine breathe to its full potential. Q8: What kind of exhaust sound upgrade should I expect on my 78 or 79 Ford truck? A8: Upgrading to these long tube stainless steel headers gives your classic Ford V8 a deep, throaty, and authentic muscle truck growl. It enhances the acoustic rumble under heavy throttle without creating a harsh, unrefined interior cabin drone, providing the perfect tone for both street cruising and trail adventures. Q9: Do these headers help prevent the common exhaust leak problems associated with classic Ford M-block engines? A9: Yes. Factory cast-iron manifolds on 351M and 400M engines are notorious for warping, cracking, and blowing out gaskets due to extreme heat stress. Flashark headers are built with thick, precision-machined mounting flanges that remain completely flat during intensive heat cycles, providing an airtight, leak-free seal that protects long-term engine health. Q10: Can I install these performance headers on a vehicle used for heavy towing or off-roading? A10: Absolutely. Heavy-duty applications are where these long-tube headers perform best. By improving exhaust scavenging, they dramatically increase mid-range and low-end torque. This extra grunt translates directly into effortless towing capacity, better hill climbing, and highly responsive torque delivery for demanding off-road conditions. Q11: Are Flashark performance headers built to strict quality control standards? A11: Yes, Flashark headers hold the ISO9001:2000 quality management certification. This ensures every set undergoes rigorous manufacturing inspections, premium welding processes, and strict fitment testing, giving classic truck restorers and car modification enthusiasts long-lasting reliability. Q12: Is free shipping available for the Flashark 1977-1979 Ford 351M 400M performance headers? A12: Yes! Flashark provides free shipping on these long tube performance exhaust headers, giving you exceptional value alongside a high-quality, race-tested upgrade for your vintage Ford truck restoration or modification project.