BC0509U – Hyundai G6DA V6 Stroker Kit – 93mm Stroke/ProH2k Rods – Unbalanced

For the builder seeking to extract the ultimate displacement and performance potential from the Hyundai G6DA V6 platform, the BC0509U Stroker Kit from Brian Crower stands as the definitive, no-compromise solution. This is not a simple crank swap; it is a fully engineered system designed to transform the 2.7L Lambda engine into a high-displacement powerhouse, laying the foundation for exceptional torque and high-rpm capability. Engineered with a massive 93mm stroke and paired with BC’s flagship Pro Series H-Beam connecting rods, the BC0509U kit delivers a calculated displacement increase to approximately 3.2 liters—a gain of over 18%—fundamentally altering the engine’s volumetric and dynamic characteristics. Supplied in an unbalanced state to accommodate custom piston selection and precise balancing for your specific rotating assembly, this kit represents the pinnacle of modular, professional-grade engine building for the G6DA, found in vehicles like the Genesis Coupe, Kia Stinger, and Sonata 2.0T. It is the core component for those targeting serious forced induction builds or high-output naturally aspirated applications where cubic inches are the ultimate advantage.

Engineering the Foundation: The 93mm Stroker Crank & ProH2k Rods

The heart of the BC0509U kit is the billet 4340 chromoly steel crankshaft, machined to exacting tolerances to achieve the aggressive 93mm stroke. This increased stroke is the primary driver behind the significant displacement bump, dramatically increasing the engine’s swept volume per revolution. This translates directly to a substantial increase in torque output across the entire rev range, improving throttle response and reducing turbo lag—a critical advantage in forced induction applications. The crankshaft is meticulously CNC-machined from premium-grade material, ensuring optimal grain structure and strength to handle the immense stresses imposed by high cylinder pressures and elevated rpm limits. It features upgraded fillet rolling for enhanced fatigue resistance at the journal radii, the points of highest stress concentration.

Connecting this robust crank to the piston is a set of Brian Crower’s renowned ProH2k Series H-Beam connecting rods. Fabricated from 4340 chromoly steel and finished with a precision machine-honed I-beam design, these rods offer an exceptional strength-to-weight ratio. The “H” beam profile provides optimal resistance to compressive and tensile loads, critical for preventing rod buckling under high boost or nitrous oxide injection. Each rod is weight-matched and Magnaflux inspected for flaws, ensuring consistency and reliability. The inclusion of ARP 2000 cap screws, renowned for their tensile strength and clamping force, secures the rod cap with maximum integrity, virtually eliminating cap walk and fretting under extreme conditions. This combination of a long-stroke crank and bulletproof rods creates a rotating assembly capable of supporting power levels well in excess of 800+ horsepower with the appropriate supporting modifications.

Strategic Design for Maximum Flexibility & Performance

Brian Crower’s decision to supply the BC0509U as an unbalanced kit is a strategic one, catering to the serious engine builder. This approach provides maximum flexibility, allowing you to select your preferred piston brand, compression ratio, and ring package to perfectly match your fuel, induction, and power goals. Once the entire rotating assembly (crank, rods, pistons, and harmonic balancer) is assembled, a professional balancing service can precisely match all components. This results in a neutrally balanced assembly that minimizes destructive harmonics, reduces bearing wear, and allows the engine to rev more freely and smoothly. This process is essential for longevity and stability at high rpm. The kit is designed to work with the stock cylinder block with a proper machining procedure to clear the increased stroke, typically involving a careful “notching” of the block and potentially cylinder honing to accommodate new piston dimensions.

Key Benefits of the BC0509U Stroker Kit

• Substantial Displacement Increase: Achieves approximately 3.2L from the 2.7L G6DA block, delivering a foundational gain in torque and horsepower potential.
• Unmatched Rotating Assembly Strength: The billet 4340 crankshaft and ProH2k 4340 chromoly rods with ARP 2000 bolts form an assembly built for extreme boost and rpm.
• Builder-Centric Flexibility: Unbalanced configuration allows for custom piston selection and perfect dynamic balancing tailored to your specific build components.
• Enhanced Engine Dynamics: The increased stroke improves low-end and mid-range torque characteristics, optimizing performance for both street and track applications.
• Foundation for High Horsepower: Provides the core mechanical strength necessary to reliably support 800+ horsepower goals with proper fueling and turbocharging.
• Professional-Grade Quality Control: Every component undergoes rigorous inspection, including Magnaflux testing on rods, ensuring reliability under stress.

Vehicle Fitment & Application Notes

The BC0509U Stroker Kit is engineered specifically for the Hyundai G6DA (Theta/Lambda) 2.7L V6 Dual CVVT engine. This engine is found in a range of performance-oriented platforms. It is absolutely critical to verify engine code and consult with your machine shop or Brian Crower for the latest application data prior to purchase. Professional installation, including block clearancing, balancing, and blueprinting, is mandatory for a successful and reliable build.

Primary Applications Include: Hyundai Genesis Coupe (BK1, BK2) 2.0T (G6DA swap), Hyundai Sonata NF (2.0T), Kia Optima TF (2.0T), Kia Stinger (2.0T), and other vehicles utilizing the G6DA long block. Note that moving to this stroker configuration will require a comprehensive retuning of the engine management system (ECU) to accommodate the new displacement, altered volumetric efficiency, and any changes in compression ratio. This build is ideal for those undertaking a full engine overhaul or building a dedicated race engine. For an in-depth technical analysis on building a high-horsepower forced induction V6, consider reading this resource on modern turbo V6 engine building principles.

Technical Specifications: BC0509U Stroker Kit