For B18B1 engine enthusiasts looking to optimize their crankcase ventilation, understanding the Positive Crankcase Ventilation (PCV) system and how to modify it with an oil catch can is crucial. This guide delves into PCV delete and oil catch can installation on B18B1 engines, specifically addressing OBD2 considerations and aiming for enhanced performance and engine health.
Understanding the B18B1 PCV System
The B18B1 engine, found in vehicles like the 94 LS Integra, utilizes a PCV system to vent crankcase gases back into the intake manifold to be burned. This system normally includes a PCV valve and a breather chamber, sometimes referred to as a “black box.” Interestingly, there are variations in the B18B1 PCV setup depending on the year. Earlier models, like those found in the 1994 Integra LS, typically have the PCV valve located on the back of the engine block, positioned above the breather chamber. Later B18B1 iterations, specifically in 1995 and newer models, relocated the PCV valve to the valve cover and eliminated the external breather chamber.
This difference in PCV valve location and breather chamber presence is key when considering modifications like a PCV delete and oil catch can installation. For owners of the earlier B18B1 engines with the block-mounted PCV valve, understanding the stock configuration is the first step before making any changes.
Why Consider a PCV Delete and Catch Can?
While the stock PCV system is designed for emissions and basic engine function, performance enthusiasts often consider modifications like a PCV delete and oil catch can for several reasons:
- Preventing Oil in the Intake Manifold: The PCV system can sometimes allow oil vapors and blow-by gases to enter the intake manifold. This oil can reduce the octane of the air-fuel mixture, leading to decreased performance and potential carbon buildup in the intake and on valves. An oil catch can is designed to trap this oil before it reaches the intake.
- Improving Engine Performance: By preventing oil recirculation, you maintain a cleaner intake system and potentially improve combustion efficiency. Some believe this can lead to slightly enhanced engine performance and throttle response.
- Extending Engine Longevity: Reducing oil and contaminants in the intake system can contribute to cleaner combustion and potentially extend the life of components like valves and catalytic converters.
- Optimizing Crankcase Ventilation: For modified engines or those driven hard, improving crankcase ventilation is essential to relieve pressure buildup, which can lead to oil leaks and other issues.
PCV Delete and Catch Can Setup Options for B18B1 (OBD2)
For B18B1 engines, especially those with the earlier PCV system configuration, there are a couple of common approaches to PCV delete and oil catch can installation. Let’s explore these setups in detail, referencing the setups mentioned in the original user’s query:
Setup 1: Breather Chamber Barb Fitting
This setup focuses on utilizing existing ports and simplifies the oil catch can integration. Here’s a breakdown:
- Remove the Breather Chamber (Black Box): Start by removing the factory breather chamber located near the back of the engine block.
- Install Barb Fitting (Fitting A): With the breather chamber removed, you’ll find a larger opening on the block where it was mounted. Install a “barb” fitting into this hole. This fitting will serve as a drain point in this setup.
- Catch Can Connection: Connect one port of the oil catch can to the PCV valve (still located on the back of the block in this configuration). Connect the other port of the catch can to the original crankcase ventilation port – this is the port that was positioned just above the breather chamber in the stock setup.
- Catch Can Drain (Using Fitting A): The “Fitting A” installed in the breather chamber hole is now used as a drain for the oil catch can. You can run a line from the bottom of the catch can to this fitting, allowing collected oil to drain back into the engine. Note: Draining back into the engine is generally discouraged in performance applications as the collected fluid is often contaminated. It’s generally recommended to manually drain the catch can periodically.
Pros of Setup 1:
- Relatively simple to implement, utilizing existing ports.
- Potentially allows for a drain-back system (though manual drain is recommended).
Cons of Setup 1:
- May not be the most efficient crankcase ventilation setup compared to other methods.
- Draining back into the engine sump can reintroduce contaminants.
Setup 2: Freeze Plug Fittings
This setup is more involved but aims for potentially improved crankcase ventilation by tapping directly into the back of the engine block:
- Remove Freeze Plugs: Locate the two freeze plugs on the back of the B18B1 engine block. Carefully remove these freeze plugs.
- Install Barb Fittings: Replace the removed freeze plugs with two “barb” fittings. These fittings will become the primary crankcase ventilation points.
- Catch Can Connection: Connect these two barb fittings directly to the two inlet ports on the oil catch can.
- PCV Valve and Other Ports: In this setup, you are essentially bypassing the original PCV valve location and breather chamber ports for crankcase ventilation. The original PCV valve port on the block can be capped or plugged. The port that was above the breather chamber can also be capped or left open to atmosphere with a small breather filter if desired (though this is less common and may not be emissions compliant). The original breather chamber is no longer used.
- Catch Can Drain: The drain plug on the oil catch can can be used for manual draining. The user in the original post mentioned connecting the drain to the oil filter area, but this is not a standard or recommended practice for oil catch cans.
Pros of Setup 2:
- Potentially offers superior crankcase ventilation by directly venting from the block.
- Completely isolates the catch can system from the intake manifold (if PCV valve port is capped).
Cons of Setup 2:
- More complex installation requiring freeze plug removal and fitting installation.
- Requires more decisions about what to do with the original PCV system ports.
OBD2 Considerations
For OBD2 compliant B18B1 engines (1994+), a PCV delete and oil catch can installation, when done correctly, should not directly trigger any check engine lights or OBD2 related issues. The PCV system is primarily related to emissions, but these modifications are generally considered to be within acceptable limits for OBD2 systems, especially if the PCV valve itself is still present in some form (even if rerouted to the catch can).
However, it’s important to ensure that any modifications are done carefully and that there are no vacuum leaks created during the process. Vacuum leaks can definitely trigger OBD2 codes related to fuel trim and air intake.
Important Note: Emissions regulations vary by location. While a PCV delete and catch can may not trigger OBD2 errors, it’s essential to be aware of and comply with local emissions laws.
Conclusion
Choosing the right PCV delete and oil catch can setup for your B18B1 engine depends on your goals and comfort level with modifications. Setup 1 is simpler and utilizes existing ports, while Setup 2 offers potentially enhanced ventilation but is more involved. Regardless of the setup, the key benefits are reducing oil in the intake, potentially improving performance and contributing to engine longevity. Always prioritize proper installation, leak checks, and be mindful of local emissions regulations when modifying your PCV system. For optimal performance and peace of mind, consider consulting with a professional mechanic experienced with Honda B-series engines.
