Flexplate 153T SFI Internal Balance

The Flexplate 153T SFI Internal Balance from ALLSTAR PERFORMANCE is a precision-engineered component engineered for high-performance engine builds requiring exact rotating mass compensation. Built for serious engine builders and street/strip enthusiasts, this internal balance flexplate eliminates the need for external balance weights on your crankshaft and torque converter assembly. When upgrading to a stroker crank, changing cam profiles, or running an aggressive fuel injection system, balancing becomes critical to prevent harmonic vibration and costly bearing wear—making the right flexplate selection essential for engine longevity and reliability.

The 153-tooth design accommodates late-model small-block and big-block applications where tooth count directly matches your engine's crankshaft sensor and ignition trigger requirements. SFI certification means this flexplate has been rigorously tested and approved for safe operation in competition and high-horsepower applications, providing peace of mind during full-throttle acceleration and launch. Internal balance technology distributes counterweight mass within the flexplate itself, allowing you to pair it directly with an internally balanced crankshaft and internally balanced torque converter without additional external weights that can complicate installation or reduce ground clearance in tight engine bays.

This flexplate is ideal for builders transitioning from carbureted to fuel-injected platforms, upgrading displacement, or pursuing serious track performance where engine harmonics directly impact reliability and power delivery. Ensure your torque converter is also internally balanced to achieve true system balance and avoid vibration issues; the 153-tooth specification is non-negotiable and must match your crankshaft's sensor ring and ignition trigger. Installation requires proper torque sequence and a quality flexplate-to-crankshaft spacer kit to guarantee concentricity and eliminate run-out that could cause converter shudder or premature transmission failure.