After diligent development, EQ has added a new performance version of the GM bolt set to its head bolt line. The HB350P is a high tensile performance oriented bolt with the cost conscious engine builder in mind. This bolt is intended for use in a high stress race related environment or for use in the daily engine building shop.
EQ head bolts are designed and manufactured to be one of the strongest bolts available. EQ’s material has a minimum ultra tensile strength of 175,000 psi. Because it is 7/16”-14 size, each head bolt has a converted minimum ultimate tensile strength of 19,150 lbs. EQ recommends torquing these bolts to 65-70 foot lbs. At this torque, normally the bolt will experience about 12,000 lbs of tensile loading. This is easily within the limits of its strength.
EQ head bolts come standard with a combination phosphate and oil finish and no additional lubrication is required. However, EQ cautions the engine builder to use extreme care if sealants are involved, to avoid accidental over-torquing. When using a sealant, lower the torque value to 55-60 foot lbs.
CAUTION: You MUST check thread engagement when installing on aftermarket cylinder heads.