Upgrading the exhaust is one of the most effective bolt-on changes you can make to a Holden VE or VF Commodore LS V8. But “exhaust” covers several different parts, and the right combination depends on your engine, your build plans and how you use the car. This guide explains what each part does and how to choose.
The three main upgrades
1. Long-tube headers
Headers (also called extractors) replace the restrictive factory manifolds. On an LS V8, a set of equal-length long-tube headers improves exhaust scavenging — each cylinder helps pull the next one clear — which frees up real horsepower and torque and sharpens throttle response. They are the single biggest power gain in the exhaust system and the foundation of any serious VE/VF build.
2. High-flow catalytic converters
High-flow cats flow far better than the restrictive factory units while keeping the car street-legal and quiet enough for daily driving. They are usually bought together with headers as a “headers & cats” package. You can choose metal-core (typically 100-cell) or ceramic-core cats depending on your power level and budget.
3. Cat-back system
The cat-back is everything from the cats to the rear of the car — the mid-pipes, mufflers and tips. This mostly determines sound and drone rather than peak power. Many VE/VF owners keep a quality cat-back (such as a twin 2.5″ or 3″ system) and add headers and cats in front of it.
Which setup should you choose?
- Stock or mild street car: 1¾″ equal-length headers with high-flow cats deliver the best balance of power, sound and drivability and bolt straight to a factory or aftermarket cat-back.
- Cam or head-and-cam build: Step up to stepped headers (for example a triple-stepped 1¾″ → 1⅞″ → 2″ design) to maintain exhaust velocity down low while flowing more up top.
- Forced induction / high-boost: Larger primaries and 3″ piping suit higher output; ceramic-core cats help with heat.
Pipe size: 2.5″ vs 3″
2.5″ suits most naturally aspirated street and mild-cam builds and keeps strong low-end response. 3″ is better for bigger head-and-cam combinations and higher-output engines where flow matters more than low-rpm velocity.
Why fitment matters on a VE/VF
Ground clearance is a real-world problem on lowered Commodores. Well-designed headers achieve true long-tube primary length while retaining factory ground clearance and bolting up without cutting or O2 extensions. Ramjet’s REX headers are engineered specifically for this — designed, tested and built in Melbourne for Australian VE/VF cars.
Frequently asked questions
Will headers fit my VE or VF Commodore? Quality LS headers bolt straight onto VE & VF V8s (LS1, LS2, LS3, L77, LSA) using factory mounts. Ramjet headers are direct bolt-on with no cutting.
Do I need a tune after fitting headers and cats? A tune is recommended to realise the full power gain, but is not required for fitment.
Will high-flow cats throw a check-engine light? High-flow cats are designed to keep the car street-friendly; a proper tune resolves any sensor issues.
How much power will I gain? Gains depend on your engine and tune, but headers and high-flow cats are the biggest bolt-on exhaust gain available on an LS VE/VF.
Ready to choose? Browse the full range of Holden VE & VF Commodore exhaust and headers, or call the team who builds them on +61 452 071 148 for build advice.