Think engine balancing is just about drilling a few holes in a counterweight? You’re only seeing half the picture.

In this masterclass from the Engine Performance Expo, Randy Neal, president of CWT Industries, reveals the hidden enemy of horsepower and durability: harmonics.

Randy goes beyond static balancing to explore the violent, dynamic world inside a running engine. Learn why a perfectly balanced crank can still tear itself apart from torsional vibration, how every engine has a unique harmonic “personality,” and why modern crankshaft and damper design is radically changing to survive today’s immense power levels. This is a must-watch for any builder looking to maximize both power and longevity.

Key Takeaways You’ll Learn:

✅ Why harmonics is a measurable science, not voodoo (explained with the powerful tuning fork analogy).
✅ How torsional flex turns crankshaft counterweights into vibrating stress points that destroy main bearings.
✅ The critical importance of modern crankshaft snout design and why the damper must be moved closer to the main bearing.
✅ Why a damper tuned for one engine setup like naturally aspirated is useless on another like nitrous or boosted.
✅ The dangerous second-order vibrations unique to flat-plane cranks (like the Ford Voodoo & Chevy LT6) and how they affect the entire vehicle.

⏱️ Timestamps:

00:00 – Introduction: The Trade-off Between Power and Durability
02:22 – Engines Under Load: The Static vs. Dynamic Reality
04:45 – From “Voodoo” to Science: The Evolution of Balancing
06:40 – What are Harmonics? The Tuning Fork Analogy
09:30 – The Real World is Not a Perfect Sine Wave
13:30 – Why Every Engine Has a Unique Harmonic “Personality”
17:00 – Learning from Failure: Predicting Explosions at Ford
21:10 – The Killer in the Crank: Understanding Torsional Load
25:10 – The Problem with Pro Mods: Committing Financial Suicide on the Burnout
27:50 – Second-Order Vibration: The Danger of Flat-Plane Cranks
31:40 – How Harmonics Can Disrupt the Valvetrain
36:00 – Visualizing Crank Flex with FEA (Finite Element Analysis)
38:50 – Bearing Forensics: What Your Bearings are Trying to Tell You
41:00 – The True Role of a Harmonic Damper (It Contains, Not Eliminates)
44:10 – The “Flagpole” Problem: Modern Crank Snout Design
49:00 – Heavy is the New Strong: Why Modern Blocks are Gaining Weight
51:40 – The Dangerous Myth of Excessive Bearing Clearance
55:00 – Modern Balancing: Why We Don’t Drill Counterweights Anymore
59:00 – Understanding Static Imbalance with Modern Software
1:02:00 – Final Thoughts: You Don’t Know What You Don’t Know
1:04:15 – The Gyroscopic Problem: Why Sprint Cars Don’t Run Dampers