Why Wrx Oil Pans Outperform The Rs Models

The Subaru WRX and STi oil pans have been a topic of discussion among car enthusiasts, with some debating the advantages of one over the other. The WRX oil pan is known for its rusting issues, while the STi oil pan has a reputation for being a better design. When it comes to performance, the STi oil pan excels, especially in track conditions, due to its ability to control oil and keep it near the oil pickup. This is crucial for preventing oil starvation and potential engine damage. However, the WRX oil pan has its advantages, such as increased oil capacity and ground clearance. Ultimately, the choice between the WRX and STi oil pans depends on individual preferences, vehicle specifications, and intended usage.

The WRX oil pan is deeper and has better oil control

The WRX pan's horizontal baffles help with oil control at lower cornering speeds and allow for increased ground clearance. However, they have performance downsides. Under more severe cornering and acceleration, the oil can pool on the horizontal baffles, preventing good flow to the bottom of the pan and the oil pickup inlet. This is why early-generation WRXs tended to have more oiling-related issues, especially on the track.

The WRX oil pan's design also restricts the header choices available. The WRX pan is a lot more restrictive for header choices than the STI version, not just limited to EL or twin-scroll header interference but also others. The STI pan has a more compact design, which offers additional clearance that can be used with the majority of aftermarket equal-length headers.

Upgrading to an aftermarket WRX oil pan can help prevent oil starvation, reduce oil temperature, and improve overall lubrication efficiency. This is especially beneficial for those who participate in high-performance driving or have modified their engines.

The WRX oil pan is more restrictive for header choices

The newer, tubbed versions of the STi pan allow for the use of higher-performance twin-scroll equal-length OEM manifolds or aftermarket equal-length headers. The WRX pan is a lot more restrictive for header choices than the STi version, not just limited to equal-length or twin-scroll header interference but also others as well. If you want equal length, the only way to go is with a new pan.

The WRX oil pan is better for track use

The WRX oil pan's flat bottom style allows the oil to move around the bottom of the pan more freely, which can be advantageous for oil control at lower cornering speeds and increased ground clearance. However, under severe cornering and acceleration, the oil can pool on the horizontal baffles, preventing good flow to the bottom of the pan and the oil pickup inlet. This can lead to oil starvation and potential engine damage.

The STi oil pan's tubbed design, on the other hand, allows for more direct oil flow to the bottom of the oil pan, ensuring a reliable supply of oil to the engine, even under the most severe track conditions. This design helps to maintain good oil condition and keep oil temperatures in check.

Additionally, the WRX oil pan is more restrictive when it comes to header choices. The STi oil pan's design allows for the use of higher-performance twin-scroll equal-length OEM manifolds or aftermarket equal-length headers, providing more flexibility for track use.

While the WRX oil pan has its advantages, particularly for daily driving, the STi oil pan's improved oil control and flow make it a better choice for the demands of track use.

The WRX oil pan is a good fix for oil delivery issues

The WRX oil pan is also better at keeping the oil near the oil pickup, which is important for ensuring adequate oil supply to the engine. The WRX oil pan's design allows for more severe cornering and acceleration without oiling issues. This makes it a good choice for those who take their cars to the track or drive aggressively.

In addition to improving oil delivery, the WRX oil pan also allows for the use of higher-performance twin-scroll equal-length OEM manifolds or aftermarket equal-length headers. This gives car enthusiasts more options for customizing their vehicles.

When considering an oil pan swap, it is important to note that the oil pickup must match the oil pan it is designed for. The WRX oil pan requires a different oil pickup than the RS oil pan, and using the wrong oil pickup can lead to oil delivery issues. It is also recommended to use a new oil pump and to replace the oil cooler if the vehicle is equipped with one.

Some car owners have shared their experiences with WRX oil pans, stating that they have had fewer issues with oil delivery and better performance on the track. However, it is important to note that some people may not agree with the need for a WRX oil pan, especially for on-road driving. It is always a good idea to consult with a mechanic or a professional before making any modifications to your vehicle.

The WRX oil pan is not a good option for all road driving

The WRX oil pan is not a good option for all-road driving. While the WRX oil pan has its benefits, it is not designed for the demands of all-road driving. Here are some reasons why:

• Oil Starvation Issues: The WRX oil pan has been associated with oil starvation issues, which can occur when the oil pickup breaks. This problem can lead to serious engine damage if not addressed promptly.
• Oil Control: The WRX oil pan, especially the older versions with flat bottoms, offers less effective oil control compared to the STi oil pan. The flat bottom design allows oil to move more freely, which can be detrimental during cornering and acceleration.
• Oil Sloshing: The WRX oil pan's design provides more room for oil to slosh around, particularly during hard cornering. This can lead to oil starvation and potential engine damage.
• Header Restrictions: The WRX oil pan is more restrictive when it comes to header choices. It may not be compatible with certain headers, limiting your options for customization or upgrades.
• Performance on Track: While the WRX oil pan is suitable for occasional spirited driving, it may not be optimal for frequent or intense track use. The STi oil pan is generally preferred for track conditions as it provides better oil control and supply.

In summary, while the WRX oil pan can be sufficient for casual driving and offers some advantages in terms of oil capacity, it falls short in critical areas such as oil control and compatibility with headers. For all-road driving, it is essential to prioritize oil management and engine reliability, making the WRX oil pan a less desirable option.

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