Complete Cylinder Heads- Unported

Cylinder Heads / Top End Kits - Complete Cylinder Heads- Unported

For many Pontiac V8 builders, a foundational step in performance is the upgrade from heavy, restrictive factory cast iron cylinder heads to modern, lightweight aluminum castings. While highly-specialized CNC porting unlocks maximum horsepower, starting with Unported Complete Cylinder Heads is often the most intelligent and cost-effective route for moderate street performance and high-torque builds.

Butler Performance provides unported, ready-to-install aluminum heads—primarily from Edelbrock—offering a massive, immediate upgrade in airflow, weight savings, and reliability over decades-old factory iron castings, all while maintaining excellent street manners.

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Cylinder Heads / Top End Kits - Complete Cylinder Heads- Unported - D-Port Cylinder Heads
D-Port Cylinder Heads
Aluminum D - Port Cylinder Heads These heads use the stock Pontiac D-Port exhaust port exits for use with standard D-port aftermarket exhaust systems. Performer Pontiac heads are...More Details »
Cylinder Heads / Top End Kits - Complete Cylinder Heads- Unported - Rd-Port Cylinder Heads
Rd-Port Cylinder Heads
Edelbrock Performer RPM heads produce outstanding horsepower with excellent low speed torque and throttle response. Designed for 1965-79 389-455 c.i.d. Pontiac engines, these heads are patterned...More Details »
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Bare Castings Round and D-Port

More About Complete Cylinder Heads- Unported

The Immediate Advantage of Aluminum

 

Choosing an unported aluminum head kit from Butler Performance, such as the widely popular Edelbrock Performer RPM D-Port or Round Port castings, provides instant benefits:

  • Weight Reduction: Aluminum heads weigh significantly less than their cast iron counterparts (often saving over 50 pounds off the front end of the car), which immediately improves handling and weight distribution.1

     

     

  • Superior Heat Dissipation: Aluminum transfers heat faster than iron. This allows builders to safely run higher compression ratios (up to 0.5 to 1 full point higher) on pump gas without detonation, translating directly into more power and efficiency.

  • Enhanced Reliability: The castings are brand new, free from the cracks, corrosion, and wear that plague used factory iron heads.

 

Complete and Ready-to-Install

 

The "Complete" aspect of these heads is key. Butler Performance ensures the unported aluminum castings arrive ready to bolt onto the short block, saving the builder significant time and machine shop costs.

The standard complete package includes:

  • Premium Castings: Brand new Edelbrock D-Port or Round Port aluminum heads.

  • High-Quality Valves: Oversized, stainless steel intake and exhaust valves, often featuring severe-duty materials.

  • Performance Springs: Matched valve springs, retainers, and locks specifically chosen to handle the lift and stress of most popular Hydraulic Flat Tappet and mild Hydraulic Roller camshafts (up to around $0.550$ inch lift).

  • Precision Valve Job: The heads receive a high-quality, precision multi-angle valve job to ensure perfect valve-to-seat sealing and optimized flow out of the box.

 

Who Should Choose Unported Heads?

 

Butler Performance recommends unported complete heads for specific build scenarios where the cost and time of CNC porting may not yield the best return on investment:

  1. High-Torque Street Engines: Engines targeting 450hp$ to 550hp and massive street torque (e.g., a stock 400 or 455 street build). The factory flow is dramatically improved by the aluminum head design, and further porting is often overkill for an engine that lives below 5,800 RPM.

  2. Budget-Conscious Builders: They offer the greatest performance-per-dollar improvement over stock iron.

  3. Future Upgrade Path: The buyer can use these heads now and send them to Butler Performance later for CNC porting when they are ready to upgrade to a more aggressive camshaft or a larger-cubic-inch stroker motor.

By supplying unported aluminum heads as complete, ready-to-go units, Butler Performance provides a smart, reliable, and powerful induction solution that forms the perfect foundation for any modern Pontiac street engine.