High-Performance Oil Pans: Worth The Cost?

When it comes to the oiling system of your engine, the oil pan plays a significant role in performance. While some may opt for a basic plastic oil pan to get the job done, there are various options available with different capacities and profiles, including open-top and sealed models. The right oil pan can help prevent messy spills and environmental damage, as well as ensure proper oil disposal. For those who enjoy getting their hands dirty and changing their own oil, choosing the right high-density oil pan is worth considering.

Aluminium vs steel oil pans

Aluminium and steel oil pans have their pros and cons. The most important factor when choosing between the two is usually the budget. Aluminium pans are generally twice as expensive as steel pans. This is due to the higher cost of aluminium as a material, the fabrication process, and the welding skills required to make them. Aluminium is typically about 50% more expensive than steel.

Another factor to consider is the weight of the oil pan. Aluminium pans are much lighter than steel pans, saving about one-third of the weight. While any weight savings can be beneficial, some people argue that this is marginalised by the fact that the oil pan is located at the bottom of the motor.

The thermal conductivity of the oil pan is also important. Aluminium has better thermal conductivity than steel, allowing it to draw more heat from the oil. However, aluminium becomes softer at higher temperatures, which can create strength problems if the oil pan is struck hard. Steel, on the other hand, can hold much higher temperatures without losing rigidity.

The structural integrity of the oil pan is a critical consideration. Fabricated aluminium pans are more prone to damage and can crack if hit hard enough. Steel pans, on the other hand, are more durable and can better withstand impacts. They hold their shape better and are often salvageable or repairable, even at the track.

In terms of aesthetics, welding a cast aluminium pan with fabricated sheet aluminium creates two very different-looking sections, which some people may not prefer.

In summary, both aluminium and steel oil pans have their advantages and disadvantages. Aluminium pans are lighter and have better thermal conductivity, but they are more expensive and less durable. Steel pans, on the other hand, are more cost-effective, stronger, and easier to repair. The choice between the two depends on the specific requirements and budget constraints of the application.

Crank scrapers

Windage trays, on the other hand, isolate the oil in the pan from the turbulence caused by the rotating crankshaft. This prevents the oil from heating up and frothing due to the agitation. Windage trays can be mounted directly to the engine's main caps or within the oil pan itself, often incorporating a crank scraper as a component.

The combination of crank scrapers and windage trays can result in notable performance gains. According to Thor Schroeder, Marketing Manager for Moroso, their use can lead to up to a five percent increase in horsepower, along with lower average oil temperatures and more consistent pressure.

Crank scraper and windage tray kits are readily available for various engine types, including LS and Vortec engines. These kits offer a cost-effective way to enhance the oiling system of your engine, improve performance, and ensure the longevity of your vehicle.

Windage trays

Windage is the flow of air within the crankcase. Each time a piston moves down in the cylinder bore, the air under it is pushed into the crank area, and when the piston moves up, the air is pulled back. Simultaneously, the rotating assembly spins and churns the air, mixing oil into it. This movement of air and oil can have a negative impact on the engine's performance.

A windage tray is an internal feature of an oil pan designed to control oil and prevent windage-related issues. It acts as a physical barrier, isolating the oil in the pan from the turbulence of the rotating crankshaft, allowing oil to return to the sump calmly and smoothly. This helps to minimise oil aeration, which can cause oil feed issues and lead to a loss of oil pressure.

The term "windage tray" has evolved to encompass different features. In some cases, it refers to the anti-slosh baffle, a sheet metal plate that covers the opening of the sump where it meets the oil pan body. This baffle is crucial for preventing oil from re-entering the rotating assembly.

The actual windage tray can be a screen or louvered piece mounted directly to the main caps of the engine or within the oil pan. It works in conjunction with a crank scraper to direct oil away from the crankshaft efficiently.

According to Thor Schroeder, Marketing Manager for Moroso, windage trays can provide up to a five per cent increase in horsepower while also lowering oil temperatures and improving pressure consistency.

Pan depth and shape

The depth and shape of an oil pan are important factors to consider when choosing the right one for your engine. The primary purpose of an oil pan is to collect oil around the pickups so that it is always available to the engine and to keep it cool. The depth of the oil pan can affect the amount of fluid it can hold, which in turn can impact heat dissipation. A deeper oil pan can allow for a greater volume of fluid, leading to improved heat dissipation.

However, engine and chassis builders often require the engine to be as low as possible, which limits the depth and volume of the oil pan. In such cases, a shallow oil pan with kickouts or power pouches can be used to increase capacity without raising the oil level. Kickouts are wings built into the bottom of the pan, allowing for greater oil volume without compromising ground clearance. Power pouches, on the other hand, are areas on the side of a non-skirted engine oil pan that allow oil vapors to escape, improving horsepower and oil temperature control.

The shape of the oil pan is also influenced by the type of engine and chassis, as well as the intended use of the vehicle. For example, a drag racing oil pan might have a trap door baffle to capture oil during deceleration, while a road racing pan needs to accommodate acceleration, deceleration, and turns in both directions. The ideal shape and design of the oil pan depend on finding the right balance between capacity and ground clearance.

Baffling

Trap-door baffles, also known as trap doors, are one-way hinged gates that allow oil to flow in one direction while impeding its flow in the other. They are designed to open inward, allowing oil to enter the chamber but not exit, thus preventing oil starvation. Fixed baffles, on the other hand, do not have moving parts and are used in conjunction with trap-door baffles to optimise oil flow.

The design and placement of baffles within an oil pan depend on its intended use. For example, a drag race pan might have a trap-door baffle to capture oil at the back of the pan, while a road race pan needs to accommodate acceleration, deceleration, and turns in both directions. The most universal design, as recommended by experts, is the road race-style pan due to its effective baffling system.

In addition to baffling, other internal features of an oil pan include windage trays and crank scrapers. Windage trays prevent the rotating crankshaft's turbulence from agitating and heating the oil, while crank scrapers catch the oil flung off the crankshaft and direct it back into the pan. Together with baffling, these features play a crucial role in oil control and ensuring the engine receives a consistent oil supply.

Frequently asked questions