EJ 300-500whp

Power Pak 1

Maximize Your Subaru's Performance

Our Power Pak 1 ncludes premium parts and expert services to elevate your combo.

Included Services and Parts:

New Cores: Fresh reliability and performance.
GSC Power Division Valves: Stock size for durability and optimal flow.
GSC5076 Spring Kit: Superior valve control under extreme conditions.

Services Include:

Rebuild with Guides: Includes disassembly, cleaning, GSC bronze guide installation, precision valve job, lash setting, milling, and professional assembly.

Power Pak 1 delivers unmatched performance and reliability for 300-500whp. This package is designed to be used with an OEM cam for ultimate performance in a street car. Contact us to get started!

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OEM Refresh

Restore Your Cylinder Heads to Like-New Condition

If you're restoring your car and returning it to stock, our Refresh Service is the perfect choice. Here’s what’s included:

Included Services:

Comprehensive Cleaning: We thoroughly clean your cylinder heads.
Valve Reconditioning: Cleaning and refacing of your valves to restore optimal performance.
Valve Seat Refresh: Ensures proper sealing and durability.
Lash Adjustment: Precisely set for proper operation.
Milling: Provides a fresh sealing surface.
Assembly: Includes brand-new Viton valve seals for long-lasting reliability.

With our Refresh Service, your cylinder heads will be restored to like-new condition, ready for years of dependable performance!

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Aftermarket Refresh

Our Subaru Aftermarket Refresh service ensures your aftermarket valvetrain is optimized for peak performance. Here’s what’s included:

Included Services:

Disassembly & Inspection: We carefully disassemble and inspect every component.
Spring Height Check: Verification of your aftermarket spring kit’s height for proper functionality.
Valve Inspection: Detailed assessment of all your aftermarket valves.
Valve Job Touch-Up: Precision adjustments to improve sealing and flow.
Lash Adjustment: Set to match your aftermarket camshafts perfectly.
Milling & Assembly: A fresh sealing surface and professional reassembly.

Important Notes:

This service is subject to compatibility. If the valvetrain components in your cylinder head do not meet our specifications for safe and reliable operation, we may decline assembly to ensure quality and performance standards.

Give your Subaru the refresh it deserves. Contact us today to learn more!

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Rebuild

Restore and Enhance Your Subaru Cylinder Heads Our Rebuild Service is the ultimate solution for worn-out valve seats or aging components, ensuring your Subaru heads perform better than new. Here’s what’s included:

Included Services:

Inspection & Diagnosis: We assess valve seat wear and identify issues caused by insufficient spring pressure from OEM springs.
Comprehensive Cleaning: Complete disassembly and thorough cleaning of all components.
Valve Reconditioning: Cleaning and refacing of your valves to restore optimal performance.
Precision Valve Job: Performed on our state-of-the-art seat and guide machine for maximum sealing and flow.
Lash Adjustment: Precisely set to ensure compatibility with your setup.
Milling: Provides a fresh sealing surface.
Reassembly: Includes installation of new Viton valve seals for lasting reliability. Experience a Rebuild That’s Better Than New. Contact us today to schedule your service!

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Rebuild w/ Guides

Required with Any Valve Upgrade

Upgrading your valves? Our Rebuild with Guides Service is essential to ensure proper valve-to-guide clearance and long-lasting performance.

Included Services:

Comprehensive Cleaning: We thoroughly clean your cylinder heads to prepare them for upgrades.
GSC Bronze Guide Installation: Installing high-performance GSC Power Division bronze valve guides and sizing them for perfect valve-to-guide clearance.
Precision Valve Job: Maximizing flow and ensuring optimal sealing.
Lash Adjustment: Precisely set to match your camshafts.
Milling: Providing a fresh sealing surface.
Reassembly: Your cylinder heads are reassembled with care, ensuring peak durability.

This process guarantees years of reliable, high-performance, boosted power! Contact us today to upgrade your valves the right way.

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Valve Upgrades

If you choose to upgrade your valves, you will need at minimum our Rebuild with Guides Service. This is necessary because the stem size of OEM valves differs from aftermarket valves. Installing an aftermarket valve in an OEM steel guide can create excessive valve-to-guide clearance, which may cause premature guide wear.

If your budget allows for a valve upgrade, we highly recommend it. OEM exhaust valves are prone to burning, which can lead to significant damage—such as destroying the heads, turbo, or valve seats.

Spring Pressure Considerations

A common concern when selecting a spring kit is adding too much spring pressure, particularly for street applications. However, when it comes to spring pressure, more is generally better than less. Insufficient pressure can lead to valve float, which can cause significant damage to your engine. Proper spring pressure ensures stable valve control and prevents potential issues at higher RPMs.

Importance of Correct Valve Spring Pressure

The right amount of spring pressure ensures the springs remain controlled, which in turn keeps the valves functioning properly. The number one cause of valve-train or cam/bucket failure is using the wrong valve spring for your application. If the valve spring isn’t up to spec, nothing else in the system will perform at its best. Proper spring selection is key to maintaining reliability and preventing costly damage.

Buckets (Lifters) and Wear

Buckets (also known as lifter or follower) are considered wearable components. The unique oiling design of the Subaru boxer engine makes them more prone to wear, as the head is the last the to receive oil, in a resulting in less lubrication and greater wear over time or during a failure. Proper replacement is essential for optimal performance and longevity.

Bucket Replacement After Engine Failure

If you’re purchasing new heads due to a recent engine failure, it's highly likely that your buckets will need to be replaced, especially if you're upgrading to a new cam. Upgrading the cam often demands additional attention to the valve-train components to ensure optimal performance and prevent further issues.

Choosing the Right Camshaft

Planning to relax in a lawn chair and listen to your car? If so, you might be tempted to go for the biggest cams on the market, and while it’ll certainly make your car sound great, it could also make it feel laggy. A camshaft that’s too large can deliver the sound you’re looking for but at the cost of drivability, especially in terms of throttle response and power delivery. Choose a cam that matches your performance goals for the best balance between sound and feel.

The Right Cam for Boosted Performance

If you love pushing your car to its limits and diving into boost on the street, a smaller cam is your best bet! We recommend sticking with stock cams up to 550whp. They provide plenty of area under the power curve, ensuring smooth, reliable performance that keeps both your dyno and your smile happy for miles of boosted fun.