What Is a Catch Can?

A catch can is a simple yet highly effective device that intercepts blow-by gases from an engine’s crankcase before they re-enter the intake system. In modern engines, the PCV (Positive Crankcase Ventilation) system routes these vapors back into the intake manifold to be burned. Unfortunately, these vapors also carry oil mist, moisture, and unburned fuel. When they contact cooler intake surfaces, they form sticky deposits that can clog intake valves, intercoolers, and even reduce octane efficiency. A catch can physically separates these contaminants from the air stream, allowing only clean air to return to the intake.

Why Your Engine Needs a Catch Can

Direct-injection engines are especially vulnerable to carbon buildup because fuel never washes the intake valves. Catch cans help mitigate this. Even port-injection engines benefit from reduced oil contamination, which can foul sensors and lower combustion efficiency. By trapping oil and moisture, a quality catch can keeps the throttle body, intake manifold, and valves cleaner, often leading to smoother idling, better throttle response, and extended oil life.

Types of Catch Cans at Nashville Performance

Nashville Performance stocks a range of catch cans engineered for different vehicle setups, driving styles, and budgets. Understanding the distinctions ensures you pick the right system for your platform.

Basic Catch Cans

These are entry-level units designed for daily drivers or mild builds. They typically consist of a simple metal or plastic canister with internal baffles or mesh to coalesce oil droplets. A basic catch can is cost-effective and straightforward to install — often just a few hose clamps. While they lack advanced filtration or vapor sealing, they still capture a significant percentage of oil mist. They are ideal for street vehicles that do not see extreme track use.

Sealed Catch Cans

Sealed catch cans are airtight units that prevent any vapors from escaping into the engine bay. They are preferred in emissions-regulated areas and for owners who want to minimize under‑hood odors. These cans often feature O‑ring-sealed caps and threaded fittings. Because they are completely enclosed, they can generate slightly higher crankcase pressure if not properly vented, so they work best with a functional PCV system. Many sealed cans include a drain port for easy emptying.

Breather Catch Cans

Breather catch cans are designed for vehicles that run open crankcase ventilation — often found on older engines, race cars, or high‑boost builds where PCV valves are removed. These cans have a vented cap or filtered outlet that allows excess vapors to escape harmlessly into the atmosphere (in off-road or track-only applications). The internal chamber still traps oil, but vapors are not recirculated. Breather cans are simple, highly effective at preventing oil ingestion, and require regular cleaning of the vent filter.

Customizable Catch Cans (Modular Systems)

For enthusiasts who want a tailored solution, modular catch cans offer interchangeable components. You can add or remove drain valves, sight windows, dipsticks, and different internal baffle types (e.g., baffle plates vs. filter media). Some systems allow you to switch between sealed and vented configurations by swapping the cap. These are popular among tuners who experiment with different engine configurations or who want the flexibility to upgrade later.

High-Performance / Race Catch Cans

Built from billet aluminum or stainless steel, high-performance catch cans use advanced internal engineering — such as cyclonic separation, coalescing filters, or multi‑stage vapor chambers — to remove nearly 100% of oil aerosol. They are designed for sustained high-RPM operation and high‑boost applications. Many include check valves to prevent reverse flow during idle or deceleration. These cans are heavier and more expensive, but they provide the highest level of protection for forced‑induction engines or race motors.

How to Choose the Right Catch Can for Your Vehicle

Selecting a catch can is not one-size-fits-all. Consider these factors when browsing Nashville Performance’s inventory.

Engine Type & Induction

Naturally aspirated engines produce less blow-by than forced‑induction engines. A basic or sealed catch can often suffices for a mild street motor. Turbocharged and supercharged engines generate much higher crankcase pressure and oil volume, so a high-performance or modular can with a larger capacity is recommended. Direct‑injection engines benefit most from any catch can to prevent carbon buildup.

Vehicle Usage: Street vs. Track

Daily drivers should prioritize sealed systems to avoid oil smells and comply with emissions. Track cars can use breather cans for maximum vapor evacuation, but must be checked frequently. If you compete in sanctioned events, check rules — some classes require sealed cans or specific materials.

Capacity & Drain Access

Catch cans range from 2 ounces for tiny single-cylinder engines to over 1 liter for V8s. A larger can needs less frequent emptying. Drain valves (ball valve or petcock) simplify maintenance — look for a can with a bottom drain that can be accessed without removing the can itself.

Material & Build Quality

Aluminum is lightweight and dissipates heat well, but cheap die-cast aluminum can leak. Billet aluminum or TIG-welded stainless steel offers durability. Avoid plastic catch cans as they can crack under engine heat or pressure.

Installation Tips

Proper placement and routing are critical. Install the catch can between the PCV valve (or valve cover outlet) and the intake manifold. The can must be lower than the intake inlet to allow gravity drainage. Use high‑temperature silicone hoses rated for oil and vacuum. Ensure all connections are clamped tightly — leaks cause unmetered air entering the intake, leading to idle issues. Many kits include brackets and hardware; if not, purchase a universal mounting bracket.

If your engine has two valve covers, consider a dual‑can setup or a single can with dual inlets. For turbo cars, also consider an oil separator before the PCV valve to protect the turbo seals.

Maintenance: Keeping Your Catch Can Effective

A catch can only works if it is emptied regularly. The collected fluid is a mix of oil, water, and fuel — it should never rise to the top of the can or be sucked back into the intake. Check the can every oil change. For a daily driver, that means every 3,000–5,000 miles. For race cars, empty after every event. Clean the internal baffles or filter media with brake cleaner or solvent if they become clogged. Replace any degraded hoses or gaskets. A neglected catch can becomes a liability rather than a benefit.

Benefits of Using a Catch Can (In Detail)

  • Reduces carbon buildup on intake valves — especially critical for GDI engines; a catch can can significantly delay or prevent the need for walnut blasting.
  • Prevents oil contamination of the intake manifold and intercooler — oil pools reduce charge air cooling and can cause detonation.
  • Maintains engine efficiency — cleaner air‑fuel mixture improves combustion consistency.
  • Extends engine lifespan — fewer deposits reduce ring wear and valve guide wear.
  • Improves overall vehicle performance — smoother idle, better throttle response, and potentially more power from reduced knock tendency.

Common Misconceptions

One misconception is that a catch can will void a vehicle warranty. While some dealers may object, aftermarket parts cannot automatically void a warranty — only if a failure is directly caused by the part. Another myth is that catch cans are only for high‑performance cars. In reality, every gasoline engine produces blow-by; a basic can on a commuter car still helps keep intake tract clean and reduces oil consumption. Finally, some people believe catch cans need to be emptied daily — if your can overflows that fast, your engine has a serious blow-by problem that needs mechanical attention.

External Resources for Further Reading

Final Considerations

Choosing a catch can from Nashville Performance means matching the product to your specific engine, driving style, and budget. A basic can is a low‑cost insurance policy; a high‑performance unit is essential for extreme builds. Whatever you pick, install it correctly, maintain it regularly, and your engine will thank you with cleaner operation and longer life. For personalized assistance, Nashville Performance’s team can help you identify the right part number, hose fittings, and mounting hardware for your vehicle.