Holden Torana LC & LJ 5.0 V8 With EFI Heads Custom Exhaust Headers EXT503
$2,295.00
Tax included
EXT503 Headers – Holden Torana LC LJ 5.0L V8 EFI Heads
EXT503 performance headers (extractors) are Australian-made tuned-length headers designed for Holden Torana LC & LJ models fitted with a 5.0L Holden V8 using EFI cylinder heads. Featuring large 44mm (1¾") primary pipes and 76mm (3") outlets, these headers are designed for high-performance street applications where increased exhaust flow and strong V8 performance are required.
EXT503 headers are made to order with an approximate manufacturing lead time of 6–8 weeks. Correct engine positioning is critical for header clearance and fitment.
EXT503 Headers – Holden Torana LC LJ 5.0L V8 EFI Heads
EXT503 high-performance headers (extractors) are designed for Holden Torana LC & LJ models fitted with a 5.0L Holden V8 using EFI cylinder heads.
Featuring a tuned-length design with large 44mm (1¾") mandrel-bent primary pipes and 76mm (3") outlets, the EXT503 is designed to provide the exhaust flow capacity required for performance Holden V8 applications. The tuned header design improves exhaust scavenging, reduces restriction and supports stronger engine performance across the usable rev range.
These headers are designed to fit with a front-mounted sway bar. Due to the limited space available in the LC/LJ Torana engine bay, correct engine positioning is essential for proper header clearance and fitment.
Key Features
- Australian Made
- Designed for Holden Torana LC & LJ
- Suitable for 5.0L Holden V8 with EFI cylinder heads
- Tuned-length design for street and high-performance applications
- Mandrel-bent 44mm (1¾") primary pipes
- Large 76mm (3") outlets
- Designed to improve exhaust flow and scavenging
- Heavy-duty header flanges
- Quality welded construction
- Fits vehicles using a front-mounted sway bar
- Made to order
Specifications
- Part Number: EXT503
- Vehicle: Holden Torana
- Series: LC & LJ
- Engine: Holden 5.0L V8
- Cylinder Heads: EFI Heads
- Header Design: Tuned Length
- Primary Pipe Size: 44mm (1¾")
- Secondary Pipe: N/A
- Outlet Size: 76mm (3")
- Construction: Mandrel-bent steel
- Manufacture: Australian Made
Fitment Notes
- Designed for Holden Torana LC & LJ fitted with a Holden 5.0L V8 using EFI cylinder heads.
- Engine must be positioned correctly for these headers to fit.
- Designed to fit with a front-mounted sway bar.
- Engine conversions can vary considerably. Engine mount position, transmission, steering components and other modifications can affect header clearance.
- Check engine position and surrounding clearances before ordering.
- Suitable header gaskets are available separately – see DSF063.
- For a scratch-free installation, protect the header surfaces during trial fitting.
- Professional installation is strongly recommended for converted LC/LJ Torana applications.
Made to Order
EXT503 headers are made to order. Please allow approximately 6–8 weeks for manufacturing before dispatch.
Manufacturing lead times are approximate and may vary depending on current production workload. Please contact us before ordering if you require the headers by a particular date.
What's Included
- EXT503 Left & Right Header Assemblies
Recommended With
- DSF063 exhaust header gaskets
- 76mm (3") performance exhaust system
- Suitable high-flow mufflers
- New exhaust mounting hardware where required
Why Good Headers & Exhaust Systems Matter
At 4,000 rpm, a naturally aspirated 5.0L four-stroke V8 theoretically displaces approximately 10,000 litres of intake air per minute at 100% volumetric efficiency. When heated to approximately 600°C, the corresponding exhaust gas occupies substantially more volume.
At 6,000 rpm, theoretical intake displacement increases to approximately 15,000 litres per minute at 100% volumetric efficiency, placing significantly greater flow demands on the headers and exhaust system.
The EXT503's large 44mm primary pipes and 76mm outlets are intended for performance applications where reducing exhaust restriction and maintaining effective gas flow become increasingly important as engine speed and power output increase.
Warranty & Compliance
- Correct engine positioning and installation are essential for proper fitment.
- Modified engine mounts, steering, transmission or chassis components may alter available clearance.
- Warranty applies to manufacturing defects and does not cover incorrect fitment, vehicle modifications, labour or consequential costs.
- Verify emissions, noise and registration compliance applicable in your state or territory.
Frequently Asked Questions
What vehicles do EXT503 headers suit?
EXT503 headers are designed for Holden Torana LC & LJ models fitted with a 5.0L Holden V8 using EFI cylinder heads.
Do these headers suit original early Holden V8 cylinder heads?
These headers are specifically listed for EFI cylinder heads. If your engine uses earlier-style Holden V8 cylinder heads, contact us before ordering so the cylinder head and exhaust port configuration can be confirmed.
What size are the primary pipes?
EXT503 uses 44mm (1¾") primary pipes with large 76mm (3") outlets.
Will they fit with a front-mounted sway bar?
Yes. EXT503 is designed for applications using a front-mounted sway bar.
Why is engine position important?
The LC/LJ Torana engine bay has limited clearance around a V8 conversion. Even relatively small differences in engine height or fore-and-aft position can affect header clearance. The engine must be correctly positioned for proper fitment.
Are the headers made to order?
Yes. EXT503 headers are made to order. Please allow approximately 6–8 weeks for manufacturing before dispatch.
Which gaskets are required?
We recommend DSF063 exhaust header gaskets, available separately.
Are these headers Australian made?
Yes. EXT503 headers are Australian made.
Do you ship Australia wide?
Yes. Best Mufflers ships headers and exhaust components throughout Australia.
Customer Support
For phone orders, advice, or part enquiries – contact us:
📞 Call Now: +61 2 9547 3511 ✉️ Email Us
🇦🇺 Best Mufflers
87A Planthurst Road, Carlton NSW 2218, Australia
Mon–Fri 8:00am–5:00pm (by appointment only)
Exhaust Systems Since 1983
EXT503
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EXT503 Headers – Holden Torana LC LJ 5.0L V8 EFI Heads
EXT503 performance headers (extractors) are Australian-made tuned-length headers designed for Holden Torana LC & LJ models fitted with a 5.0L Holden V8 using EFI cylinder heads. Featuring large 44mm (1¾") primary pipes and 76mm (3") outlets, these headers are designed for high-performance street applications where increased exhaust flow and strong V8 performance are required.
EXT503 headers are made to order with an approximate manufacturing lead time of 6–8 weeks. Correct engine positioning is critical for header clearance and fitment.