Manley Size STD Stroke 79mm Bore (99.50mm Grade A) SINGLE Piston w/ Rings WRX STI EJ257 2004-2021

Part #: 612000CA - 1. Manley Subaru pistons are crafted from high - strength 2618 material. They offer drop - in installation and match OEM Grade Range A or B bore sizes. Just pick the right grade of pistons for your engine block. Each grade has the proper clearance designed in. These pistons come with Premium Chrome Moly 0.180' wall pins, great for moderate boost. Also included are Total Seal piston rings. The top ring is AP steel, and the second has a Napier profile for better oil control. For high - boost engines, it's highly advised to install 9310 alloy 0.210' wall wrist pins (part no. 42546).

Using these Manley pistons is straightforward. First, make sure to select the appropriate grade range pistons that match your engine block's requirements. The pistons are designed for drop - in installation, so they should fit right in. When it comes to the pins, if you're using the engine under moderate boost, the standard Premium Chrome Moly 0.180' wall pins will work well. But for high - boost situations, replace them with 9310 alloy 0.210' wall wrist pins (part no. 42546). As for maintenance, regularly check the piston rings for wear. The Total Seal piston rings are of good quality, but over time, they may need to be replaced. Keep an eye on the oil control too, as the Napier profile of the second ring helps with that. If you notice any decrease in performance or strange noises, it might be time to inspect the pistons and rings more closely.