- Improved performance

G02 X4 M40i

"SP (Anti-surge)" - 4

CP-Carrillo pistons are the best choice for any M60 B30 or B40 engine and application

Our Oversized Kit option utilizes ARP's proprietary Custom Age 625+ material option combined with specialized insert washers for ultra-high boost applications

ARP Head Stud Kit, BMW M50 M52 S50 S52 11mm Oversized 4048 - Improved performanceThis ARP oversized 11mm head stud kit is designed to replace the 10mm head studs in M50 M52 S50 S52 engines for those who want to push the limits of their high horsepower turbo engines. However, it's a MUST to have the block drilled and tapped professionally prior to installation. These head studs are a great choice for increasing boost levels without the cylinder head lifting. While both the 11mm L19 and 10mm Custom Age 625+ head studs are high