These are the highest quality and strongest Head Studs available on the market. We would recommend these for anyone looking to build their VR38 motor. Consider these an insurance policy for your head gasket... If you're looking to make big power (proven over 1000+whp) but don't like the idea of lifting your cylinder head and replacing head gaskets frequently these are exactly what you need! These studs are manufactured specifically for us by A1 Technologies and utilize an H11 material that is much stronger than the typical 8740 chromoly and yields a tensile strength of 260,000 psi. They are also provisioned with a hex broach on the top of the stud enabling you to install them with the cylinder head on the car if necessary. What is so different about these head studs? At first glance these may appear to be similar to the other ARP and A1 Technologies head studs available on the market, but that is simply not the case. The MAP Ultimate Duty Head Studs include an additional feature known as a "dog point" (shown below) that seats the stud in the block and preloads the fastener for an accurate and repeatable torque sequence..