The Butler Process

Every engine Butler Performance builds follows the same rigorous process developed over six decades of Pontiac experience. We don't cut corners, and we don't rush — because an engine that isn't built right will eventually let you down, and that's not how we operate.

Step 1 — Consultation

We start by understanding your build. What's the car? What's the chassis? Street driver, weekend bracket racer, show car, or dedicated drag car? What are your horsepower goals, and what's your budget? We match every component to the application from the very beginning — not after the fact.

This is where most builds go wrong: parts chosen without understanding the system. We prevent that by asking the right questions upfront.

Step 2 — Core Inspection & Preparation

If you're supplying a core block, it gets fully disassembled, hot-tanked, and magna-fluxed for cracks. We check main bore alignment, deck height, and bore condition before committing to any machining plan. Cores that don't pass inspection are set aside — we won't build on a compromised foundation.

Step 3 — Precision Machining

All machining is performed in-house on our Haas UMC-750P 5-axis CNC machining center and supporting equipment:

• Boring and honing to target bore size and surface finish
• Block decking to correct deck height and squareness
• Main align-boring where required
• Head surfacing and port matching
• Custom CNC work as specified

Every operation is documented. You'll know exactly what was done and to what specification.

Step 4 — Component Selection & Assembly

Components are selected specifically for your application. We work with Ross Pistons for custom forged pistons, COMP Cams for our exclusive Butler-spec cam grinds, Edelbrock for cylinder heads and intake manifolds, and a range of other top-line suppliers for bearings, gaskets, and hardware.

Assembly is performed to factory-manual torque specifications with ARP fasteners throughout. Every clearance — rod side clearance, main bearing clearance, ring end gap — is measured, documented, and within spec before the engine is assembled.

Step 5 — Dyno Verification

Every complete engine Butler Performance builds is run on our Superflow Dyno before it ships. The dyno session serves two purposes: break-in and verification. We run the engine through a proper break-in cycle, then pull it to redline to verify horsepower and torque output.

You receive a certified dyno printout with your engine showing peak horsepower, peak torque, and the RPM at which each was achieved. Not estimates — actual documented numbers from your engine.

Step 6 — Shipping

Engines are drained, cleaned, and packed for freight shipping in a wooden crate. We include all documentation: the dyno sheet, break-in instructions, torque specs, and a parts list for every component used in the build. Everything you need to install and run the engine correctly is in the box.

Ready to start your build? Call us at (931) 829-2200 or contact us online.