CP Piston & Ring Set for 4G63 2G-Bore (85.0rmm)-Size (STD)-CR (8.5 Eclipse / 9.0 Evo 8/9)

This is a set of forged pistons and rings from CP Pistons, specifically made for the Mitsubishi 4G63 engine. These are designed for the second generation (2G) bore size, measuring 85.0mm, and come in a standard size. The compression ratio is set at 8.5:1, which is suitable for the Eclipse, or 9.0:1 for the Evo 8 and 9 models, offering a choice depending on your specific build goals.

CP Pistons are well-known in the performance engine building world. These pistons are forged from high-strength aluminum alloy, which makes them incredibly durable and able to withstand the higher cylinder pressures and temperatures found in modified or performance-oriented 4G63 engines. The standard bore size means they are a direct replacement for stock dimensions, simplifying installation if you're rebuilding your engine to its original bore. The included rings are matched to the pistons to ensure a proper seal within the cylinder walls, which is critical for compression and oil control.

When building a performance 4G63, especially one that will see boost or higher RPMs, forged pistons like these are a significant upgrade over cast pistons. They offer much greater resistance to detonation and fatigue. Keep in mind that these pistons are not CARB approved and cannot be shipped to California. For optimal performance and longevity, it's recommended to consult with your engine builder or refer to CP Pistons' technical documentation for specific installation and break-in procedures.