BC0916-75 – Polaris XP Turbo (16-up) Stroker Kit 75mm w/Carrillo Rods

The Ultimate Foundation for Dominant Forced Induction Power

For the serious Polaris XP Turbo builder, the pursuit of maximum horsepower and relentless durability is a non-negotiable engineering challenge. The factory rotating assembly, while robust for stock configurations, becomes the primary limiting factor when pushing the boundaries of boost pressure and RPM. The BC0916-75 Stroker Kit is not merely an upgrade; it is a complete re-engineering of the engine’s core, transforming the ProStar 900 twin into a displacement-enhanced powerhouse engineered for the most extreme turbo and nitrous applications. This comprehensive system from Billet Crankshaft Company pairs a meticulously machined 75mm stroker billet crankshaft with legendary Carrillo connecting rods, offering a choice of top-tier forged pistons to create the definitive foundation for your high-performance build. It is the critical component set for those who define performance by torque under the curve, unwavering reliability at the limit, and supremacy in any terrain or competition.

Precision Billet Crank Engineering: The Heart of the Stroke

At the core of the BC0916-75 kit lies a crankshaft that redefines strength and precision. Unlike a modified OEM casting or a lesser-quality forging, this component is CNC-machined from a single, aerospace-grade 4340 steel billet. This manufacturing process ensures the grain flow of the metal is continuous and unbroken, resulting in a crankshaft with superior fatigue resistance and ultimate tensile strength. The 75mm stroke represents a significant increase over stock, yielding a substantial displacement gain that translates directly to increased torque and horsepower, particularly in the critical mid-range where races are won. Each crank is statically and dynamically balanced to exacting tolerances, minimizing destructive harmonics that can lead to bearing failure in high-RPM, high-boost environments. The journals are micro-polished to a mirror finish, promoting optimal oil film retention and reducing friction for both increased power and longevity.

Carrillo H-Beam Rods: The Unbreakable Link

Connecting the increased stroke of the crankshaft to the piston is a task that demands the best in the industry. This kit includes genuine Carrillo H-beam connecting rods, the undisputed gold standard in high-performance motorsports. Manufactured from premium 4340 steel and utilizing Carrillo’s proprietary manufacturing and heat-treating processes, these rods offer an unparalleled strength-to-weight ratio. The H-beam design provides exceptional resistance to buckling and compressive loads encountered under extreme cylinder pressure from turbocharging. The attention to detail is evident in the precision-machined big end and small end, ensuring perfect bearing alignment and fit. Utilizing Carrillo rods eliminates the connecting rod as a potential failure point, allowing you to focus your tuning efforts on extracting maximum power without fear of mechanical catastrophe. For an in-depth look at the metallurgy and design philosophy behind such components, industry leaders like Engine Labs provide valuable technical analysis on selecting connecting rods.

Forged Piston Selection: Tailoring Compression and Geometry

Recognizing that every build has unique goals, the BC0916-75 kit offers a critical choice in piston selection, allowing you to tailor the compression ratio and design to your specific fuel and boost strategy. Each option is a purpose-built, forged piston designed for the increased stroke and cylinder pressures.

• CP Pistons: Renowned for their race-proven durability and advanced design. CP utilizes 2618 aluminum alloy, ideal for extreme boost and nitrous applications where cylinder pressures are immense. Their designs often feature reinforced ring lands and optimized skirt profiles for stability.
• JE Pistons: A staple in the performance world, JE pistons offer exceptional quality and a wide range of dome configurations. Their 2618 alloy forgings provide excellent strength, and their proprietary skirt coating reduces friction and wear during critical cold-start periods.
• BME Pistons: Known for innovative design and lightweight construction. BME pistons can offer advantages in reducing reciprocating mass, allowing for higher engine speeds and reduced stress on the rotating assembly, a key factor in high-RPM turbo applications.

All piston options are precision-matched to the increased stroke and rod length, ensuring correct deck height and valve clearance. The included piston rings are high-quality, low-tension sets designed to seal immense combustion pressure while minimizing parasitic drag.

Vehicle Fitment & Application

The BC0916-75 Stroker Kit is engineered specifically for the Polaris ProStar 900 platform used in XP Turbo models. Correct fitment is paramount for performance and reliability. This kit is designed as a direct replacement for the OEM rotating assembly in the following applications:

• Polaris RZR XP Turbo (All Models) – 2016, 2017, 2018, 2019, 2020+
• Polaris RZR XP 4 Turbo (All Models) – 2016, 2017, 2018, 2019, 2020+
• Polaris General XP 4 Turbo – 2019, 2020+

Critical Installation Note: Installation of this stroker kit requires expert engine machining and assembly. It is mandatory to have the engine block cylinder bores measured and honed to match the exact piston size and geometry. Professional balancing of the entire rotating assembly (crankshaft, rods, pistons, and flywheel/clutch) is highly recommended for optimal smoothness and longevity. This kit is intended for experienced builders or professional engine shops.

Performance Benefits & Technical Advantages

• Substantial Displacement Increase: The 75mm stroke significantly increases engine displacement, generating more torque and horsepower across the entire RPM band, particularly enhancing low-end and mid-range response which is critical for turbocharged applications.
• Unmatched Rotating Assembly Strength: The billet 4340 steel crankshaft and Carrillo 4340 steel rods create a virtually indestructible foundation, capable of handling well in excess of 300+ horsepower and massive boost levels with complete reliability.
• Reduced Engine Stress at High Power: The increased displacement allows you to achieve your target power level with lower boost pressure compared to a stock-stroke engine, resulting in lower intake air temperatures, reduced cylinder pressure spikes, and overall a more efficient and stable tuning window.
• Superior Bearing & Oil System Life: The micro-polished crank journals and precision-fit Carrillo rods ensure ideal oil film thickness and flow, drastically reducing wear on crankshaft and rod bearings even under severe duty cycles.
• Future-Proof Foundation: This kit establishes an engine platform that can support multiple tiers of future upgrades, from larger turbos to aggressive camshaft profiles, without ever needing to revisit the bottom end.

Technical Specifications

Installation Imperatives for Maximum Performance

To realize the full potential and durability of the BC0916-75 kit, professional installation is not a suggestion—it is a requirement. The engine block must be disassembled, thoroughly cleaned, and measured. Cylinder bores must be honed on a torque plate to match the new pistons perfectly, ensuring optimal ring seal and longevity. The oiling system, including the pump and relief valve, should be inspected and upgraded if necessary to support the increased demand. Pair this rotating assembly with a performance camshaft, valvetrain, and fuel system capable of supporting your power goals, and manage it all with a properly tuned ECU. When installed with this level of precision, the BC0916-75 Stroker Kit transcends being a part; it becomes the cornerstone of a legendary Polaris XP Turbo powertrain that delivers dominant, reliable power wherever the throttle is opened.