4P 625+ Extreme Duty Head-Studs

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  • Regular price $595.00
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4 Piston Racing Head Stud Kit for Honda/Acura B & K Series (B18C1, B18C5, B20VTEC, LSVTEC, K20, K24, K20C1 Type-R, k20c4)

These studs are made exclusively for 4 Piston by ARP to be the absolute best for your racing engine.  There is no other material on the market better suited for cylinder head clamping.  625+ material is substantially stronger than any entry level 8740 head stud material, and substantially stronger than L19.  L19 is subject to hydrogen embrittlement and stress corrosion.  Even if handled properly during the assembly process, L19 is exposed to condensation inside a running engine.  There is nothing you can do to avoid this. Furthermore,  625+ has a yield strength 17% greater than L19 and 30% greater than 8740.

Build your engine with the absolute best from 4 Piston, and turn the boost up!  Make sure you select the correct engine in the drop-down menu.

·Each kit includes a complete set of 625+ head studs, nuts, washers, ARP Assembly Lubricant, and installation instructions.