* Specific year and model of the engine: Even within the "Vortec 350" designation, there were variations over the years. The block casting number will be the most definitive identifier.
* Head bolt type and material: The head bolts themselves might be different strengths.
* Main bearing cap bolt type and material: Similar to head bolts, the material of the main bearing cap bolts is crucial.
* Torque sequence: The order in which the bolts are tightened is just as important as the torque itself. Improper sequencing can lead to distortion of the block.
You absolutely MUST consult a factory service manual specific to your engine's year and model. This manual will provide the correct torque specifications and tightening sequence. Using incorrect torque specs can lead to serious engine damage, including cracked blocks or blown head gaskets.
Trying to find the information without the precise engine details is risky and could result in costly repairs. The engine casting number (typically found on the side of the block) will help you locate the correct service manual.
