A-Series ARP HSA11 Head Stud Set.
Used by KAD and recommended for all performance A-Series engines.
High quality materials ensure cylinder head can be tightened down effectively and studs will not stretch over time like cheap copies.
Set includes 11 head studs. We recommend modifying your engine for the extra 2 studs.
2 Lengths of front studs are available -
Standard length - more for road base engines where threads in the block have not been deepened and minimal skimming from both block and cylinder head.
Long - used on all our race builds, requires extra drilling and threading with the block and counter boring for better stud location. Measurements of studs are as follows -
Total length – 4.250”
3/8UNC / Block thread – 0.700”
3/8UNF / Head nut thread – 1.250”
Head nut and washer height – 0.500”