what do extractors actually do performance wise?

Answer 1

in which type of machine are these extractors used?there are mant types of extractors but what machine or device are they used in?

Answer 2

Exhaust Extractors

Answer 3

An extractor is another name for a header, which is to say, the part of the exhaust system that bolts to the engine, but it's usually a specific KIND of header.

An extractor is basically a set of tubes that bolt to the engine at one end and to a collector (the place where all the tubes come together) at the other. When the piston pushes the exhaust out of the cylinder on the fourth part of the combustion cycle (suck, squish, bang, blow), you can think of the exhaust leaving the cylinder as a "pulse."

When this pulse leaves the tube and goes into the collector, the pressure in the tube portion drops, creating a partial vacuum. Think of this as a "negative pulse." (This negative pulse, by the way, travels at the speed of sound.)

What makes extractors work is that when each pulse hits the collector and its negative pulse bounces back up the tube, it can actually help the NEXT pulse get out of the combustion chamber because there's this partial-vacuum right at the exhaust valve. If it's all timed just right, the extractor sucks the exhaust out of the cylinder, which has two benefits:

1 - Less work is required to push the exhaust out into the tube. Result: More power at the crankshaft.

2 - If the intake valve and the exhaust valve are open at the same time, having this little vacuum at the exhaust can actually help suck in some of the intake charge a little early. This means there will be more air/fuel mix in the cylinder, and you'll make more power because there's more stuff to burn.

The tricky part is the timing. For every length and diameter of tubing, there will be one engine speed at which everything is just right -- a "sweet spot" -- because the speed at which the vacuum travels up the tube is fixed, but the time between combustion cycles varies depending on how fast the engine is turning, how long the cam keeps the valves open, and a LOT more. In general, shorter pipes work better at high RPM (because the vacuum pulse travels up the pipe in less time, the cycles have to be closer together for this to work) and longer pipes work better at low RPM (because a longer pipe makes the vacuum take longer to get to the exhaust valve). Similarly, wider tubes are better for flowing a high volume of exhaust, and narrower tubes are better for flowing exhaust at high velocity.

The decision of where to put this "sweet spot" depends on what you're designing for. If you're building a car to have a wide torque curve, you might want to put this "sweet spot" at a low spot in the torque curve, to sort of beef it up and give the car more acceleration across the band. If you're building a car with a 7-speed gearbox, you can put the sweet spot at the strongest point of the car's powerband to make even MORE power at that one, focused spot, because your gearbox will let the driver keep the engine in this double sweet spot all the time.

Answer 4

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what do extractors actually do performance wise?

Answer 5

De-catting your car does improve the flow of your exhaust, but not too much, just depends on the vehicle. The high-flow cats are mainly for people who live in states that have strict emissions laws. I live in California, and anything that you do to modify your vehicle that does not have a CARB sticker on it will automatically make you fail the visual inspection. De-catting would also cause a fail. If your state requires that you have a cat on your car during smog testing, then I advise you to custom weld some flanges onto the de-cat pipe and onto your existing pipe so that you can remove and install your cat in case you need it. Overall, it increases exhaust flow so it does allow more exhaust to escape efficiently with little restriction.