What Does a Catch Can Do?

Your cars engine has a very intricate way of taking care of itself. For example, when oil blowby occurs, the engine is set up to recirculate the oil through the engine again, however, that can lead to power loss over time unless you install an oil catch can. But what is a catch can and is it illegal to install one in your car?

The end result is that your engine will have cleaner valves and combustion chambers over time. While smog laws can vary by state, it is typically illegal to install an oil catch in your cars engine bay, according to SmogTips.com.

Does a catch can add horsepower?

An oil catch can doesn’t add any power or make any cool noises so it is often overlooked when modifying vehicles. However, a catch can will ensure you always have a cleaner intake tract free of oil, and help keep your engine running better for longer.

Is a catch can really necessary?

It should be noted that oil catch cans are only really necessary for direct injection engines. Unlike other engines, direct injection engines do not have fuel regularly cleaning the valves and are therefore more likely to experience the formation of carbon deposits.

Why are catch cans illegal?

Although a catch can could help your car’s engine run well for a long time, modifying the PCV system is illegal since it’s part of the engine’s emissions system. If a technician were to see an oil catch can installed on your car while performing an emissions test, they may fail you on the spot.

Do catch cans affect performance?

Power numbers will be low, as blow by pressure will have a significantly harder time exiting the head than when sucked out by the catch can. The result is the following: catch cans will have an impact on your racing speed. They keep engines clean and vent power robbing pressure from your engine’s cylinder heads.

There is a large debate as to whether or not oil catch cans are worth the money or not. This article is dedicated to providing a very detailed explanation showing why a catch can is highly recommended in direct injection engine applications.

So the PCV system removes the pressure from the crankcase and reverts it back through the intake tract via crank case vents. You might ask why do car manufacturers revert this crankcase pressure back into the intake tract?

Well, for starters there isn’t anywhere safe to revert it, and you can‘t expel it into the atmosphere because it’s not environmentally friendly and is considered to not be street legal. Most people don’t even change their oil at proper intervals (scary but true) so will they think to empty a catch can regularly? A more pure air mixture entering the intake valves means no caking and none of the symptoms listed above.

An oil catch can doesn’t add any power or make any cool noises so it is often overlooked when modifying vehicles. However, a catch can will ensure you always have a cleaner intake tract free of oil, and help keep your engine running better for longer.

Your engine is a violent place. It’s filled with moving metal, hot oil and fuel, and a mass of moving air. All of that combines to create combustion, which is basically a series of continual explosionsand it’s all happening right in front of you.

An oil catch can is a device designed to let air back into the intake system, while restricting oil particles from re-entering along with it. When a piston moves up and down in the cylinder some of the combustion gets past the sides of the pistons into the crankcase. This is known as blow-by. Through the PCV (Positive Crankcase Ventilation) valve, that pressure is allowed to return back into the air intake system where it can be used again and burnt off in a subsequent combustion cycle.

The baffle located inside is a metal plate acting as a shield that lets only air slip past into the outlet hose.

What is oil blow-by?

In order to understand what an oil catch can is, you first need to know what oil blow-by is. In a typical four-stroke engine, there is an intake stroke, which lets the air-fuel mixture into the cylinder; the compression stroke, which compresses that air/fuel mixture; the power stroke, which is when the spark (from the plugs) ignites the mixture and forced the piston back into the cylinder; and the exhaust stroke, which is when the exhaust gas is pushed out of the cylinder.During the compression stroke, an immense amount of pressure is built up so much that a small amount of air can escape from around the piston rings. This is called “blow-by,” and the higher the RPM your engine spins, the more blow-by it will have. Fortunately, every engine has a PCV system that vents the crankcase – and the blow-by – and routes it back into the engine’s combustions chambers to safely burn them up.