Custom 12mm ca625+ head studs Mazdaspeed3/6

Custom 12mm Head studs for the Mazdaspeed3/6.  These are the recommended head studs for over 800whp. We have tested these in vehicles making over 1300whp. These are not direct fit, and machining IS required to the block and cylinder head for fitment. Includes ARP nuts, washers, assembly lube and instructions