Gap Gang Highway Bully 128ci Top End Only Package For Road Reliability And Track Readiness

Gap Gang Highway Bully Package 128ci (Top End Only) is engineered for riders who crave serious road reliability with the edge of a track-ready punch when opportunities appear. This top-end upgrade is purpose-built to push your 128 cubic inch engine beyond stock limits, delivering crisp throttle response, expanded airflow, and measurable power gains without a full engine rebuild.

What's included in the package

• 128ci Top-End Kit — engineered to bring you to a 128 cubic inch displacement with precision components and a focused performance approach. (Includes the essential top-end hardware to maximize airflow and combustion efficiency.)
• Cam of Our Choice — a tuned cam profile selected to optimize torque on the highway and straight-line acceleration on the track.
• Pushrod Kit, S&S Lifters, Tapped Cuffs — reliability-focused valvetrain hardware designed to handle higher RPM and sustained power output.
• HPI Intake and Throttle-Body — improved intake flow and throttle response, helping you make the most of the larger displacement.
• Gap Gang Injectors — precise fueling to match the upgraded airflow, supporting clean, consistent power delivery.
• Installed & Tuned — professional installation and a optimized tune to ensure your setup performs right out of the door.

Performance potential and what it means for you

• With stock heads, you’re looking at robust, highway-friendly power—ample for confident overtakes and steady rolling power.
• Our optimized head options can add roughly an additional 15 HP, helping you cross into the 150s horsepower range and into our coveted “150s Club.”
• Designed for riders who want a seamless transition from street reliability to track-ready performance when the moment arises, the Highway Bully package delivers a predictable, repeatable power curve with strong mid-range torque for highway cruising and quick, confident acceleration on winding straights.

Who benefits most from this kit

• Riders seeking a focused top-end upgrade that survives street use and occasional track sessions.
• Enthusiasts who want a turnkey solution—cam, lifters, pushrods, intake, injectors, and a pro-tuned setup all included—without sourcing each part separately.
• Owners aiming for a measurable power increase while maintaining reliability and drivability on daily rides.

Installation, compatibility, and care

• Top-end only: requires engine disassembly and technician-level installation. A professional shop or experienced mechanic is recommended to maximize efficiency and reliability.
• Includes a dedicated tune to optimize air-fuel delivery and timing for the upgraded components, helping you achieve smooth power delivery and fuel economy consistency during break-in and daily use.
• Proper break-in and periodic tuning checks are encouraged to maintain peak performance and longevity of the upgraded top end.

Why this package stands out

• End-to-end integration: every part in the Highway Bully Package is chosen to work together—from the cam and lifters to the intake and injectors—so you don’t have to cobble parts together and chase fueling and timing issues.
• Real-world usability: designed with road reliability in mind, but tuned to unlock track-capable performance when the moment calls for it.
• Clear upgrade path: compatible with stock or upgraded heads, with an explicit horsepower trajectory that helps you plan future enhancements while staying within a coherent, proven setup.

If you’re chasing a balanced upgrade that transforms highway power with an eye on track readiness, the Gap Gang Highway Bully Package 128ci (Top End Only) offers a precise, thoughtfully assembled route to bigger power, improved response, and dependable performance—without guessing at the component mix. It’s the practical, high-performance choice for riders who demand both street bravado and weekend-ready capability.