Insert Washers - 1/4 ID (10)

ARP Insert Washers - 1/4 ID (10) are precision-engineered chromoly fastening components designed for high-performance engine assembly and critical motorsports applications. This set of 10 washers is essential for builders and performance shops working with ARP fastening systems on competitive engines, restorations, or engine rebuilds.

These washers feature a 0.562-inch outer diameter, a 0.25-inch inner diameter, and a 0.318-inch insert OD, all crafted from chromoly steel with a black oxide finish for corrosion resistance and reliable load distribution. The precision engineering ensures that the washers seat properly on ARP head bolt studs, creating uniform clamping pressure across the cylinder head surface.

Engine builders will benefit from the consistent preload and even stress distribution these washers provide, which are critical in high-boost, forced-induction, and naturally aspirated engine builds. Proper washer selection is vital to prevent gasket failure and head lift under combustion forces, making these washers a reliable choice for various engine applications.