Build Yours Like Butler

Build Yours Like Butler: Mastering the Art of the High-Performance Pontiac V8

For the dedicated enthusiast, the pinnacle of Pontiac ownership is a custom-built, high-horsepower engine. For decades, Butler Performance has set the standard for what a Pontiac V8 can achieve, consistently delivering dyno-proven power from $450\text{hp}$ street setups to extreme $700\text{hp}$ pump gas monsters.

Recognizing that many builders prefer to do the final assembly themselves or work with a local machine shop, Butler Performance created the "Build Yours Like Butler" approach. This philosophy is about supplying not just the premium parts, but the critical machine work, precise blueprinting, and expert knowledge that transforms a box of components into a world-class Pontiac engine.

Here is a look at the essential steps and principles Butler applies to every engine, which you can apply to your own build.

1. The Block: The "Butler Process" Foundation

The Pontiac block (whether an original 400, 455, or an aftermarket IA II casting) is the foundation, and Butler’s preparation process is exhaustive:

• Rigorous Cleaning: The process starts with a multi-step cleaning regimen (baking, blasting, and jet washing) to ensure the block is absolutely free of contaminants.

   

• Inspection and Testing: Every block is Magnafluxed (to check for cracks) and Sonic Tested (to verify cylinder wall thickness). This guarantees the block can safely support the intended bore size and power level.

   

• Precision Machining: Critical machining steps are performed:

  • Align Honing: The main bearing bores are precisely align-honed to ensure the crankshaft spins perfectly straight.

     

  • Torque Plate Honing: The cylinder bores are honed with a torque plate installed. This simulates the distortion caused when the cylinder head is torqued down, resulting in perfectly round cylinders when the engine is assembled—a huge boost for ring sealing and power.

     

  • Square Decking: The cylinder decks are machined perfectly parallel to the crankshaft centerline, ensuring an identical combustion ratio and a perfect head-to-block seal on every cylinder.

2. The Rotating Assembly: Flawless Balance is Key

The biggest differentiator in a Butler engine is the rotating assembly. Butler does not rely on "box balancing" (manufacturer-supplied weights); they do it in-house:

• Internal Balancing: The crankshaft, connecting rods (often H-beam for strength), and custom forged pistons are computer balanced to match perfectly, often to within less than half a gram. This eliminates destructive vibrations at high RPMs, extending engine life and freeing up hidden horsepower.

   

• Custom Stroker Kits: Butler is famous for its stroker combinations (like the $4.250$ inch stroke in a $400$ block to achieve $461\text{ci}$ or more). They provide the fully matched components—crankshaft, rods, and custom Ross pistons—that are proven to work together reliably.

   

• Ring Gapping: Butler sets performance ring gaps, typically recommending around $0.016$ to $0.018$ inches for street engines, which is vital for high-horsepower longevity and proper heat dissipation.

   

3. Valvetrain and Induction: Matched Combos

Butler’s expertise is evident in the components they match to the block. The goal is always a harmonious combination that maximizes air flow and power:

• Cylinder Heads: They utilize and often CNC-port top-tier aluminum heads (like Edelbrock's D-Port or Round Port castings). For the ultimate "sleeper" look, they offer the "Stealth Option" to remove external logos, allowing the aluminum heads to be painted to look like factory cast iron.

   
   

• Hydraulic Roller Cams: For street/strip, they specify their exclusive hydraulic roller profiles (like the Aggressive Series) with precise Lobe Separation Angles (LSAs) matched to the engine's cubic inches and intended idle quality.

• Valvetrain Control: Every cam is paired with premium components like Johnson or Morel short-travel hydraulic roller lifters and high-rate dual valve springs to maintain perfect valvetrain stability up to the redline.

   

• Fueling: The choice of induction—whether a custom-calibrated Quadrajet for the stock look, or a high-flow Holley/EFI setup—is chosen to flawlessly feed the engine's specific airflow demands.

The Final Critical Step: Pre-Assembly Check

Even when shipping a fully machined kit, Butler advises every builder to perform a pre-assembly mock-up. They emphasize checking:

• Bearing Clearances: Rod and main bearing clearances must be verified.

   

• Piston-to-Valve Clearance: Critical on large-stroke, high-lift cam combinations.

• Piston-to-Counterweight Clearance: Ensuring the stroker crank clears the piston skirts and the block webbing.

• Thrust End Play: Verifying that the crankshaft's end-play is within tolerance before and after installing the transmission.

   

By sourcing Butler’s precision-machined blocks, balanced rotating assemblies, and expertly matched component kits, you gain the benefit of their decades of racing knowledge, ensuring your final Pontiac build performs at the Butler level.