Wheat pennies and gradings what does P.D.S. mean on pennies?
Philadelphia Denver San Francisco
PDS stands for particularly dangerous situation. A PDS severe thunderstorm watch means that there is a significant chance of very severe thunderstorms capable of causing major structural damage. A PDS tornado watch means there is a significant chance of strong tornadoes. These are often issued before a major tornado outbreak.
First af all, I hope you are using new head bolts. Torque procedure is several steps: a) all bolts 15ft pds, b) all bolts 29ft pds, c) all 37ft pds. Now, one at a time back off each bolt two revolutions and torque to the following spec in sequence: LONG BOLTS 11-19 ft pds, and rotate an additional 85-95 degrees. SHORT BOLTS 7-15 ft pds and rotate an additional 85-95 degrees.