What year was 355 Chevy engine built?

There's no single year the 355 Chevy engine was built. The 355 cubic inch small-block Chevrolet engine wasn't a factory-produced engine like the 350. Instead, it's a common engine displacement achieved by aftermarket modifications to the 350 cubic inch small block. People have been building 355s since the 350 became available, meaning they've been built in numerous years.