The Chevy 302 (301 as it was called in the day) engine was a 283 CI engine bored to 4".
The SB Chevy 283 engine bored out to 301 CI was the top dog SB Chevy engine until Chevrolet introduced the 327 CI engine in 1962.
My first street machine when I graduated high school was a yellow '56 Chevy Del Ray 2-door sedan with a 265 CI Power Pack engine, 3-speed with OD. I rebuilt and installed a 1957 Chevrolet 283 CI engine in the '56 Chevy. My 283 CI engine was bored to 4.00" for 301 CI and I installed a 4.56:1 rear gear. I wrecked my '56 Chevy on December 23, 1962 and installed the 4.56 rear end in my 1959 Impala 2-dr. HT with a 4-speed.