Hurricane Headers HU345STM – Jeep Grand Cherokee WJ 4.7L V8 PowerTech 1999–2004

Hurricane Headers HU345STM are engineered to suit Jeep Grand Cherokee WJ 4.7L V8 PowerTech vehicles from 1999 to 2004. These aftermarket headers are a practical upgrade over the very restrictive factory manifolds, helping the engine breathe more efficiently while improving torque, throttle response, and exhaust flow. They are ideal for street-driven 4WDs, restoration work, and performance-minded owners wanting a stronger and more efficient exhaust setup.

Product Features

• Designed to suit Jeep Grand Cherokee WJ 4.7L V8 PowerTech 1999–2004
• Excellent replacement for restrictive factory exhaust manifolds
• 38mm primary pipes with 51mm outlets
• Thick machined flanges for improved durability and sealing
• Smooth merge collectors to improve scavenging and power delivery
• Suitable for left-hand-drive vehicles

Construction

• Manufactured from high-quality steel tubing
• Quality welded construction for long service life
• Finished in heat-resistant paint rated to 800°C
• Ceramic coating available as an optional upgrade for improved heat management and durability

Performance & Engine Airflow

The 4.7L PowerTech V8 moves approximately 9,400 litres of intake air per minute at 4000 rpm. After combustion and exhaust gas expansion, total exhaust volume can exceed 14,000 litres per minute. Hurricane Headers HU345STM help the engine evacuate this volume more efficiently than the factory manifolds, supporting improved exhaust flow and usable performance.

Fitment Notes

• Check availability before ordering
• Oxygen sensor fittings are not supplied or fitted
• Aftermarket replacement catalytic converters are required
• Will fit left-hand-drive models
• Protect painted surfaces and wrap headers during trial fitting
• Clearance may vary depending on engine mounts, steering components, and aftermarket parts
• Verify emissions and registration compliance in your state

What’s Included

• HU345STM-L Hurricane Header Left
• HU345STM-R Hurricane Header Right

Recommended With

• Header gasket set – see product code HG345
• Oxygen sensor fittings (2 required) – see product code OSN18M
• Suitable aftermarket catalytic converters to complete installation

Warranty

• Backed by Hurricane Headers 2-year warranty (standard manufacturer terms apply)

Frequently Asked Questions

Q: Do these headers fit left-hand-drive models?
A: Yes. HU345STM is listed to suit left and right hand-drive Jeep Grand Cherokee WJ 4.7L V8 models.

Q: Are oxygen sensor fittings included?
A: No. Oxygen sensor fittings are not fitted to the headers. Use product code OSN18M if required.

Q: Are gaskets included?
A: Header gaskets are recommended separately. See product code HG345.

Q: Do I need catalytic converters?
A: Yes. Aftermarket replacement catalytic converters are required to complete the system.

Q: Can these headers be ceramic coated?
A: Yes. Ceramic coating is available as an optional upgrade for improved heat control and durability. Contact us for details.

Q: Will these fit every WJ exactly the same?
A: Clearance can vary depending on engine mount condition, steering components, and any aftermarket modifications, so trial fitting is recommended before final installation.

Customer Support

For phone orders, advice, or part enquiries – contact us:

📞 Call Now: +61 2 9547 3511 ✉️ Email Us

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87A Planthurst Road, Carlton NSW 2218, Australia
Exhaust Systems Since 1983