Rated at a tensile strength 190,000 to 200,000 PSI. Material 8740 Chrome moly. U.S. made. These studs have a hex in the end to allow the user to run the studs down into the block. 12 point flat bottom nuts included.
These studs eliminate problems associated from head bolt use. Common problems include bolt breakage, block and thread damage, less clamping force and bolt stretch, constant re-torquing of cylinder head, rear oil gallery leakage. Keep that head from moving around. General fastener torque spec. 70 to 80 Ft Lbs Ultra torque lube. Be sure to add on Ultra torque lube Part# 2464 when purchasing this kit.

THE FOLLOWING INSTRUCTIONS ARE FROM ON HIGH- ARP ENGINEERS FORWARD TO US: Please be sure to clean out the block holes. These are studs are a free floating fastener so it is not necessary to Lock Tite or bottom them out and torque the studs into the block. However, it is important to have as much threaded engagement in the block as possible. The stud should not pass through the nut. Doing so will lessen the threaded engagement of the stud in the block. 3 rounds, crossing pattern on the head up to 80 ft lbs. NO need to re-torque like with old style head bolts.

SPECIAL NOTE: Original U20 head bolts were un-heat treated and have a tendency to stretch and or break off in the block. Early head bolt head diameter measures .622. Later, better quality, replacements that are currently available are $240.00 for the complete set and they measure .702. If you have the early head bolts we strongly recommend replacement with our stud kit.

SPECIAL NOTE: All of the head bolts on the passenger side of the block are the same length. It is not necessary to be concerned about the stud length where the, cylinder head, locating dowels are placed. We have found that there is enough, threaded engagement in the block, to allow a proper torque.

NOTE:Please also look at PART#'s 1152 & 2551, for important information, to determine if you need thicker lash pads if you are using a re-ground cam or thicker cam tower shims.