SBC Firing Order and Torque Specs | 350 & others
A Little History: 265 and 350 to 400
For nearly six decades now the small block Chevy engine has dominated the world of motorsports. It’s been the most sought-after V-8 engine among hot rodders and racing enthusiast since its debut in 1955. Chevrolet’s first design started in the early 1950s, and in 1955, the company released the 265 cubic inch, 162hp V-8. Soon after, Chevy released the 283 in 1957, followed by the very popular 327 in 1962. Then in 1967, Chevy had a big year with the release of the 302 and 350 engines. The 302 still used a 4-inch bore, but had a shorter 3-inch stroke like the 283, affording a much higher-winding race engine. The Chevy 350 blocks used the same 4-inch bore as the 327s, except they increased the stroke to 3.480-inches.
Jumping even later in the 1960s, Chevy made major design changes to the block, crankshaft, and connecting rod areas, including a new large-journal crank with 2.10-inch rods and 2.45-inch mains, compression heights varied, and in 1968 Chevy started to introduce new bore and stroke combinations like the 307. With the new large-journal design came reliability and it remained the same until the late 1990s, with the exception of the 400 block that used a larger 2.65-inch main journal.
Today: The LT and LS-series
We can fast forward several generations to the LT and LS-series engines which have an awesome balance of performance and reliability. Whether looking back to a remarkable history or forward to a very promising future, it’s impossible to deny credit where credit is due. When it comes to parts, the availably seems limitless, with most of them being interchangeable. Add to that, the power to cost ratio, it’s no wonder the mighty blue bow-tie has reigned over the competition all of these years.
Torque Specifications and Firing Order on SBCs
We’ve compiled some basic tips and specifications that will be helpful for anyone working on one of these popular V8s. Listed above we have a diagram of the distributor rotation, cylinder order, and firing order. Listed below are some of the most important torque specifications and torque sequences that are helpful to anyone building a small block Chevy.