Kooks 2012+ WK2 Jeep/ Durango 6.4L 1-7/8in x 3in SS Long Tube Headers - Cat SS Conn Pipe

Kooks 1-7/8" x 3" Long Tube Headers with Catted Connection Pipes for 2012+ Jeep Grand Cherokee SRT8 & Dodge Durango SRT 6.4L HEMI

The Kooks 3410H421 1-7/8-inch long tube headers and catted connection pipes kit provides a complete bolt-on exhaust upgrade for 2012+ Jeep Grand Cherokee SRT8 and 2018+ Dodge Durango SRT models with the 6.4L HEMI V8, replacing factory manifolds to deliver dyno-verified gains of 40-50 rear-wheel horsepower and 35-45 lb-ft of torque through improved exhaust scavenging and reduced backpressure.

Handcrafted from T304 aircraft-quality stainless steel with equal-length primaries, merged collectors, and high-flow catted 3-inch connection pipes that mate directly to the OEM mid-section, this system enhances throttle response across the 4,700 RPM redline while producing a deep, aggressive V8 rumble without interior drone.

The precision laser-cut 3/8-inch thick flanges and TIG-welded construction ensure leak-free sealing under high heat loads from towing, track days, or daily acceleration, supporting up to 700 HP from stock-plus tunes. For SRT owners requiring a seamless integration of performance, emissions compliance, and durability, the 3410H421 kit delivers the engineered flow path to unlock the 6.4L's full output potential in any driving condition.

Key Features

• 1-7/8-Inch Equal-Length Primaries: Mandrel-bent for uniform exhaust pulses and optimal mid-range torque delivery.
• 3-Inch Catted Connection Pipes: High-flow stainless catalytic converters with 3-inch inlet to OEM outlet for unrestricted flow.
• T304 Stainless Steel Build: 16-gauge tubing with full TIG welds for corrosion resistance and heat tolerance over 1,600°F.
• Merged Collectors: Venturi design reduces turbulence and enhances scavenging efficiency.
• Laser-Cut Flanges: 3/8-inch thick with blended ports to prevent leaks and match cylinder head contours.
• Dyno-Tested Performance: 40-50 RWHP and 35-45 RWTQ gains on stock 6.4L engines.

Product Notes

• 49-state EPA compliant not legal for use in California or CARB-adopting states without exemption.
• Fits RWD models only excludes AWD variants due to driveline interference.
• O2 sensor extensions included professional tuning recommended for maximum gains and to avoid CEL.
• California Proposition 65: Contains chemicals known to the State of California to cause cancer or reproductive harm.

Warranty: Limited lifetime on headers and construction 25,000 miles on catalytic converters.

Installation Notes

• Professional installation advised requires lift for underbody access and alignment.
• Remove factory manifolds and heat shields torque header bolts to 25-30 ft-lbs in sequence.
• Bolt connection pipes to headers and OEM exhaust using provided gaskets and clamps.
• Complete ECU drive cycle post-install to adapt O2 sensors; recheck torque after 100 miles.

This Part Fits

Note: Fits WK2 platform RWD configurations with factory exhaust routing. Verify no aftermarket modifications affect clearance.

What's Included in the Purchase

• (2) 1-7/8" x 3" Long-Tube Stainless Steel Headers with Merged Collectors
• (1) Pair of 3-Inch Inlet x OEM Outlet Catted Stainless Steel Connection Pipes
• Gaskets, Stage 8 Locking Header Bolts, and Flange Hardware
• O2 Sensor Extension Harnesses (2 x 18-inch, 2 x 6-inch)
• Exhaust Clamps and Hanger Kit
• Installation Instructions with Torque Specifications

Why Choose Kooks?

• Over 60 years of exhaust engineering, with hundreds of NHRA, NASCAR, and SCCA championships.
• Handcrafted in the USA from T304 aircraft-quality stainless steel for precision fitment.
• Limited lifetime warranty and dyno-proven designs for consistent results.

Frequently Asked Questions

• Q: Is this kit compatible with AWD models?
  A: No, designed for RWD only AWD requires custom clearance solutions.
• Q: Will it trigger a check engine light?
  A: No, with included O2 extensions and proper installation tune advised for tuned setups.
• Q: What power gains can I expect on a stock 6.4L SRT?
  A: 40-50 RWHP and 35-45 RWTQ, with more from complementary mods like intake or tune.

Shipping & Handling

• Availability: Ships within 1-2 business days custom fabrication lead times vary.
• Total Package Weight: 62 lbs | Shipping Dimensions: 48" L x 22" W x 16" H.