Manley 99.5mm STD Bore Pistons Subaru WRX 2002-2014 / STI 2004-2021 | 612000C-4

Part #: 612000C - 4. These Manley pistons for the EJ257 are forged and dished, crafted from high - strength 2618 material. They're lightweight but tough, built to last a long time. Every set comes free with round wire locks, tool steel wrist pins, and piston rings. A special multi - step machining process for the top ring groove ensures perfect control of its size, shape, flatness, and finish. Precise pinhole machining gives an exact compression distance and accurate lock ring groove spacing, size, and concentricity. Available in standard size and a wide range of oversize options, they're perfect for any high - performance engine build. Note: All Manley pistons come with a full set of four pistons, piston rings, and hardware. (99.5mm STD Bore, 8.5 Comp. Ratio)

Using these Manley pistons is straightforward. When installing, make sure to align the pistons correctly in the engine cylinders. It's a good idea to check the piston rings and hardware for any signs of damage before putting them in. As for maintenance, keep an eye on the engine's oil levels and quality. Regularly changing the oil will help keep the pistons in good shape. Also, if you notice any unusual engine noises or performance issues, it might be time to inspect the pistons. Remember, these pistons are designed for high - performance engines, so use them in appropriate setups for the best results.