About the 350 SBC Engine
The 350 Small Block Chevy (SBC) engine is a popular choice among automotive enthusiasts due to its versatility, reliability, and performance capabilities. Introduced by Chevrolet in 1967, the 350 SBC quickly became a staple in the automotive industry and has been used in a wide range of vehicles ever since. With a displacement of 5.7 liters, this V8 engine offers a balance of power and efficiency, making it suitable for various applications, including street cars, muscle cars, and even some light-duty trucks.
Head Bolt Torque Specifications
When assembling or reassembling the cylinder heads on a 350 SBC engine, it is crucial to ensure proper torque is applied to the head bolts. This ensures a secure and leak-free seal between the cylinder heads and the engine block. Here are the recommended head bolt torque specifications for a 350 SBC engine:
| Stage | Torque (ft. lbs.) | Torque (Nm) |
|---|---|---|
| Stage 1 | 30 | 41 |
| Stage 2 | 60 | 81 |
| Stage 3 | 90 | 122 |
Procedure for Torquing Head Bolts
To properly torque the head bolts on a 350 SBC engine, follow these steps:
1. Start by cleaning the threads of the head bolts and the corresponding holes in the engine block using a suitable cleaning agent.
2. Apply a small amount of engine oil or assembly lubricant to the threads of each head bolt.
3. Install the cylinder heads onto the engine block, ensuring proper alignment and gasket placement.
4. Begin torquing the head bolts in a crisscross pattern, starting from the center bolts and working your way outward. This helps distribute the torque evenly.
5. Use a torque wrench to tighten the head bolts to the specified torque for each stage. Be sure to follow the torque sequence recommended by the manufacturer.
6. Repeat the torquing process for each stage, gradually increasing the torque until reaching the final specified value.
7. After reaching the final torque value, allow the engine to sit for a few minutes to allow for any relaxation of the gasket material.
8. Finally, perform a final torque check on all the head bolts to ensure they are still properly tightened.
By following these torque specifications and the recommended torquing procedure, you can ensure a secure and reliable seal between the cylinder heads and the engine block of your 350 SBC engine. This helps prevent coolant and oil leaks, ensuring optimal engine performance and longevity.
Remember, it is essential to consult the specific manufacturer’s guidelines or service manual for your engine to ensure accurate torque specifications, as they may vary depending on the year and model of the 350 SBC engine you are working with.