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The Subaru FA20DIT engine is known for its impressive performance and efficiency, but enthusiasts often seek ways to enhance its capabilities further. One popular modification is porting the cylinder head, which can lead to significant power improvements. In this article, we will explore the installation steps for porting a Subaru FA20DIT head and the potential power gains you can achieve.
Understanding the FA20DIT Engine
The FA20DIT is a turbocharged flat-four engine that powers various Subaru models. It features a DOHC design, direct fuel injection, and an aluminum alloy construction. Understanding its components and how they work together is crucial before attempting any modifications.
- Engine Type: Turbocharged Flat-Four
- Displacement: 2.0 liters
- Power Output: Approximately 250 hp (varies by model)
- Torque: Around 267 lb-ft
Benefits of Porting the Cylinder Head
Porting the cylinder head can improve airflow, which in turn enhances engine performance. Here are some key benefits:
- Increased horsepower and torque
- Improved throttle response
- Better fuel efficiency at higher RPMs
- Enhanced overall engine performance
Tools and Materials Needed
Before starting the porting process, gather the necessary tools and materials:
- Cylinder head gasket set
- Porting tools (grinders, burrs, sanding rolls)
- Measuring tools (calipers, micrometers)
- Cleaning supplies (solvent, brushes)
- Torque wrench
- Engine assembly lubricant
Installation Steps for Porting the FA20DIT Head
Step 1: Remove the Cylinder Head
Begin by removing the cylinder head from the engine block. This involves:
- Disconnecting the battery
- Draining the coolant and oil
- Removing the intake and exhaust manifolds
- Unbolting the cylinder head and lifting it off
Step 2: Clean the Cylinder Head
Thoroughly clean the cylinder head to remove any carbon buildup or debris. Use a solvent and brushes to ensure all surfaces are free from contaminants.
Step 3: Assess the Head for Porting
Inspect the cylinder head for areas that require porting. Focus on:
- Intake and exhaust ports
- Combustion chamber
- Valve seats
Step 4: Begin Porting
Using your porting tools, start reshaping the intake and exhaust ports. Follow these guidelines:
- Remove material gradually to avoid over-porting.
- Focus on smoothing the transitions between ports and runners.
- Maintain the original port shape as much as possible.
Step 5: Polish the Ports
After porting, polish the ports to improve airflow quality. Use finer sanding rolls and polishing compounds for this step.
Step 6: Reassemble the Cylinder Head
Once porting and polishing are complete, reassemble the cylinder head. Ensure all components are cleaned and lubricated properly.
Step 7: Reinstall the Cylinder Head
Carefully reinstall the cylinder head onto the engine block, following the torque specifications provided by Subaru. Reconnect all components, including the intake and exhaust manifolds.
Achievable Power Improvements
After porting the FA20DIT head, many enthusiasts report noticeable enhancements in performance. While results may vary based on other modifications and tuning, here are some potential power improvements:
- 10-20% increase in horsepower
- Improvement in torque delivery throughout the RPM range
- Enhanced boost response from the turbocharger
Conclusion
Porting the Subaru FA20DIT head can be a rewarding modification that leads to significant power gains and improved engine performance. By following the steps outlined in this guide, you can successfully port your cylinder head and enjoy the benefits of enhanced airflow and efficiency.