Description

This ARP 145-3901 Mopar Pro Series cylinder head bolt kit comes with a reduced wrenching 12 point head. This eliminates the need for valve train removal to facilitate cylinder head retorquing. These Pro Series bolts are 220,000 psi (which is 15% stronger than Grade 8)! Kits come complete with hardened parallel-ground washers. Sold as a set of 30.

ARP 145-3901 Mopar Head Bolt Kit Features:

• Fits 426 Factory Hemi
• Also Fits Mopar 426-472-528 Hemi Crate Motor with factory heads or Edelbrock Hemi Victor Jr heads
  
• Two Lengths
• 12 Point Head
• ARP2000 – 220,000 PSI

Which is better, cylinder head studs or bolts? The answer depends on the installation. On many street-driven vehicles, master cylinders and other items protrude into the engine compartment. Its probably necessary to use head bolts so the cylinder heads can be removed with the engine in the car.

The ARP 145-3901 Mopar Head Bolt Kit is perfect for that application!

Studs also provide more accurate and consistent torque loading. Using studs ensures easier engine assembly, and proper alignment of both the cylinder head and gasket.

Heres why: when you use bolts to secure the head, the fastener is actually being twisted while its being torqued to the proper reading. Accordingly, the bolt is reacting to two different forces simultaneously.

Install a stud in a relaxed mode never crank it in tightly using a jammed nut. Always install the stud hand tight! Then, when applying torque to the nut, the stud will stretch only on the vertical axis.

Remember, an undercut shorter stud will have a rate similar to a longer, standard shank stud. This provides a more even clamping force on the head. Because the head gasket may compress, check with your gasket manufacturer for retorquing requirements.