How is a Chevy 301 made.I have read somewhere it destroked 327 but what specs?

The Chevy 301 engine is not created by destroking a 327 engine. The 301 engine is actually a variant of the Chevrolet small-block engine, which was introduced in 1955. The 301 engine was produced from 1968 to 1976 and was used in various GM vehicles, including the Camaro, Firebird, Nova, and Corvette.

The 301 engine has a displacement of 301 cubic inches (4.9 liters) and was designed to replace the 283 engine. It has a bore of 4.00 inches (101.6 mm) and a stroke of 3.00 inches (76.2 mm). The 301 engine is essentially a bored-out version of the 283 with a longer stroke. It features a two-barrel carburetor and single exhaust.

Compared to the 327 engine, the 301 engine has a smaller displacement, a shorter stroke, and a different bore size. The 327 engine has a displacement of 327 cubic inches (5.4 liters), a bore of 4.00 inches (101.6 mm), and a stroke of 3.25 inches (82.55 mm).

Therefore, the Chevy 301 engine is not made by destroking a 327 engine, but rather it is a separate engine in the Chevrolet small-block family with its own unique specifications.