Quick answer: extractors, which many people call headers, replace the factory cast-iron exhaust manifold with a set of tubular steel pipes, one for each cylinder, that merge into a collector. Their job is to let every cylinder empty its exhaust gas more freely than the stock manifold allows. In Australia the words 'extractors' and 'headers' mean the same thing.
If you have seen 'extractors' on a parts list and wondered what they do, how they differ from a manifold, or whether they are worth fitting, this guide explains it in plain language and shows the kinds of extractors in our range.
What do extractors actually do?
Every time an exhaust valve opens, a pulse of hot gas leaves the cylinder. A factory manifold is usually a heavy cast-iron casting designed to be cheap, durable and quiet, and its short, shared passages can make those pulses fight each other. Extractors give each cylinder its own tubular primary pipe, and then bring the pipes together in a carefully shaped collector. When the pipe lengths and shapes are well designed, one pulse helps pull the next one out, which is often called scavenging.
Extractors vs factory manifold
| Feature | Factory manifold | Extractors (headers) |
|---|---|---|
| Construction | Usually cast iron | Tubular steel pipes, welded to flanges and a collector |
| Design aim | Cost, durability, low noise | Exhaust flow and cylinder scavenging |
| Gas passages | Short and shared | One primary pipe per cylinder |
| Sound | Muted | Often crisper and more pronounced |
| Fitting | Original equipment | Needs matching gaskets, and sometimes extra parts |
The main types of extractor
You will see a few terms on extractor listings. They describe how the primary pipes are arranged and joined.
Tri-Y
A Tri-Y design joins the primary pipes in two stages: pairs of cylinders merge into secondary pipes, and those then merge into the collector. This layout is common on classic V8s, and it tends to favour mid-range torque.
Four-into-one
A four-into-one design brings all of the primary pipes together at a single collector. It tends to favour top-end power. Treat these as tendencies rather than guarantees, because the exact result depends on the engine, the pipe sizes and the rest of the exhaust.
Tuned
'Tuned' usually means the primary pipes are shaped and sized so that exhaust pulses arrive at the collector in an orderly way. Many modern applications, including the LS-style V8 engines, use tuned designs.
Shorty and long-tube
Shorty extractors are compact and easier to fit in tight engine bays. Long-tube extractors have longer primary pipes, which gives more room to tune the flow but takes more space and usually needs a matching catalytic converter arrangement.
Examples from our range
Our headers and extractors collection covers a wide range of vehicles. These examples show how the listings describe the design:
- Pacemaker extractors for Commodore VN to VS 5.0L V8: a Tri-Y design with 1 3/4 inch primary pipes and 2 inch secondary pipes.
- Pacemaker extractors for Commodore VT to VZ 5.7L Gen III and 6.0L LS2: a tuned design with 1 3/4 inch primary pipes and a 3 inch outlet.
- Pacemaker extractors for Commodore VS Ecotec 3.8L V6: a tuned design with 1 1/2 inch primary pipes and a 2 inch outlet.
- XForce VE/VF V8 long-tube header and 3 inch cat kit: 304 stainless steel, supplied with matched high-flow catalytic converters and a fitting kit.
You can also browse the full Pacemaker range, which covers a long list of Holden, Ford, Toyota, Nissan and other applications.
What else you will need
Extractors are rarely a single-part job, so plan for the extras before you order:
- Gaskets. Many extractor listings state the gasket code and note that gaskets are sold separately unless the listing is a kit.
- Oxygen sensor extension looms. Some applications need these so the factory sensors reach their new positions.
- Other fitting parts. Some manual-transmission applications may need a separate clutch bracket. Always read the 'please check before ordering' note on the listing.
- Catalytic converters. Extractors usually sit ahead of the catalytic converter, so choose a converter that suits your setup. Our high-flow cats for extractors are made for this job.
- A matching exhaust. Extractors work best when the rest of the system flows well too. See our guides on 2.5-inch vs 3-inch exhausts and the types of exhaust system, or pair them with a cat-back from our cat-back range.
Many of our extractors are special-order items, so delivery can take longer than a stocked part. Check the listing before you plan a fitting date.
Do extractors add power?
They can help an engine breathe more freely, and the benefit tends to be larger on engines that are already modified, but the result varies a lot with the engine, the rest of the exhaust and the tune. We would treat any specific horsepower claim with caution unless it comes from dyno testing on a car like yours. A sensible expectation is a stronger, crisper exhaust note and a more responsive feel, with the biggest gains when the extractors are part of a complete package.
How do extractors change the sound?
Because each cylinder now has its own pipe, extractors usually make the exhaust sound sharper and more defined, particularly at higher revs. The muffler and pipe size still control most of the volume, so our guide to how loud your exhaust will be is a good next read.
Are extractors legal?
Rules vary by state, and they apply to noise and to emissions equipment. Extractors that keep the catalytic converter and sensors in place are the lower-risk choice, while removing emissions equipment is not permitted on registered vehicles in several states. Our parts are intended for off-road and track use unless otherwise stated, and customers are responsible for complying with the rules that apply to them. This is general information only, not legal advice. Read our state-by-state legality guide and check with your state road authority.
Frequently asked questions
Are extractors and headers the same thing?
Yes. 'Extractors' is the traditional Australian term and 'headers' is the term used overseas. Both describe tubular exhaust manifolds.
Do I need new gaskets?
Yes. A fresh gasket is needed when fitting extractors, and many listings give the gasket code and note that it is sold separately unless the listing is a kit.
Do extractors make a car louder?
Often they make the exhaust sound sharper rather than simply louder. The muffler and pipe size decide most of the volume.
Do I need a tune after fitting extractors?
Not always, but modern engines that are managed by a computer can respond to changes in exhaust flow, and sensor positions can change. Ask the workshop that fits them, or the parts supplier, whether tuning is recommended for your engine.
Can I fit extractors myself?
It depends on the car. Some engine bays are tight, bolts can be seized, and extractors need careful alignment. Many owners choose to have a qualified exhaust workshop do it. Our compatibility guide shows how to check fitment before you order.
What is the difference between shorty and long-tube extractors?
Shorty extractors are compact and simpler to fit. Long-tube extractors have longer primary pipes for more flow tuning, but they need more space and a matching catalytic converter arrangement.
Find extractors for your vehicle
Browse our headers and extractors collection, or contact the DEA Performance team with your make, model, year and engine, and we will help you find the right set. You can also call us on 03 9793 9916.