136ci Gap Gang Performance Big Bully Package Full Build for M8 Harley Davidson High Torque Power Upgrade

Transform your M8 Harley‑Davidson into a street‑seeking, track‑ready powerhouse with the 136ci Gap Gang Preformance Big Bully Package Full Build. This turnkey bolt‑on upgrade blends aggressive displacement with race‑inspired engineering to deliver a thrilling, high‑torque, high‑rev experience. Expect roughly 170+ horsepower when paired with the right supporting parts and tuning, turning every ride into precision power and instantaneous throttle response from corner to corner.

Key components that drive the power

• 136ci displacement combined with high‑compression pistons for instant throttle response and strong top‑end power.
• Burns Big Momma Pipe designed to optimize exhaust flow, reducing backpressure and unlocking peak performance.
• Gap Gang Preformance Heads engineered to maximize airflow and breathing at high RPMs.
• S&S Top End Guardian Kit provides durable top‑end protection at elevated power levels for long‑term reliability.
• Man O War Crank and Dark Horse Sprocket deliver smooth, resilient rotation and dependable power transfer.
• S&S Cam Chest and Oil Pimp with Quickie PushRods and billet tappet cuffs for precise valvetrain timing and durability.
• S&S Oiler Jets and Fueling Short Travel Lifters ensure reliable fueling under load and during high‑demand riding.
• Cam Of Our Choice lets you tailor the powerband to your riding style and preferred scenarios.
• 136Ci Cylinders paired with high‑compression pistons for consistent power delivery across the rev range.
• Install Labor and Tune included — a true turnkey experience that arrives dialed‑in and dyno‑verified so you can ride from day one.

Why this kit stands out

This isn’t a generic bolt‑on. It’s a cohesive, race‑inspired package that integrates top‑end protection, enhanced airflow, and precise fueling with a tuned powerband. The combination of high‑flow heads, an optimized exhaust path, a beefy bottom end, and a carefully crafted valvetrain ensures power stays linear and controllable from low RPM to peak horsepower. With installation labor and a professional tune included, you get a ready‑to‑ride machine that performs at the level you expect from a purpose‑built M8 hot rod.

Who this is for

Designed for riders who demand maximum street‑ready performance from an M8 platform while preserving reliability under high horsepower. This is the turnkey solution for enthusiasts who want a professionally supported build that arrives already dialed in, with the confidence that comes from premium components working in harmony.

Ideal use cases and scenarios

• Street riders seeking brutal torque and a rapid throttle response for confident overtakes and first‑gear pulls.
• Long highway trips where predictable power delivery and robust fueling keep you cruising smoothly.
• Track‑oriented weekend rides where a tailored powerband and durable top end let you push the bike harder with less maintenance worry.