These 9/16" to 1/2" custom head studs were originally designed for use in Top Fuel. They are much larger than the commonly used 11mm head studs and requires the block to be tapped to 9/16-12.
Torque can be increased up to 125 ft lbs. Cylinder honing required after installation with torque plates. Some cylinder heads will require stud holes to be reamed to accommodate larger 1/2" stud. May require shorter dowel pins.
Includes 20 studs, 20 nuts and 20 hard washers. Not recommended on iron blocks.
