ZRP Forged Pistons for BMW 2.5L M52 Single Vanos 85.00mm 8.3:1

BMW 2.5L M52 (Single Vanos) pistons are developed for a moderate to high-level build, mainly for street or club racing cars that desire to build their engine for high mileage and/or street use. Designed by ZRP engineers and manufactured in Germany from high silicon, low expansion 4032 (T6) alloy. This enables the engine builder to use a smaller piston to bore clearance, resulting in a better seal. This minimizes cold start piston slap noise, common with engines using forged pistons, providing quiet operation and low oil consumption. We have chosen a full-round skirt design with a bottom reinforcing band, with oversized and deeper valve pockets to allow the use of high-lift camshaft profiles. They have offset pins for quiet operation and the piston pins are made from 9310 alloy. Other features include anti-detonation grooves to protect the top rings, gas pressure accumulator groove for better ring sealing, and vibration relief. Premium Japanese quality 1.00mm x 1.20mm x 2.80mm ring pack included. Product Features & Design Anti-detonation grooves for extended life and performance Gas pressure accumulator groove at the second ring land for extended life. Horizontal grooves on the pin bore designed to allow oil to get between the piston pin and the pin bore area. CNC precision machined ring grooves 4032-T6 High Silicon/Low Expansion Alloy Polished pin bores Clip cuts on intake side edge Full round skirt design with bottom reinforcing band for high HP/Boost applications Valve pockets designed to allow oversized valves and high lift camshafts Pistons designed to optimize compression for increased engine life and increased horsepower potential Optional coatings offered on request "Blast Off Bronze" thermal barrier coating "Stealth Black" molybdenum side skirt and under crown coating