1

How-To

Blacksheep Speed&Fab

Head stud torque pattern on flathead straight 8.

Hello everyone, Blacksheep speed and fab here just demonstrating the proper torque pattern for my Packard thunderbolt flathead straight 8. The basic pattern can be used with most large flatheads with starting from the center and working your way out.

All you need is

-1/2 drive torque wrench

-Socket set

In steps of 15lbs, 40lbs, and final of 65lbs, torque the head bolts in the following order, this was the torque spec for my head, you will have to look yours up prior to working.

Heres a vintage image of the pattern.

To get the most accurate torque on each stud, make sure you clean and if necessary chase the threads with a tap and die before torquing.

Thats it! Make sure you re-torque after a couple heat up and cool down cycles.