The 265 Chevy small block was a revelation when introduced in 1955 being light, simple, durable and most of all powerful. The design featured pressed steel rockers, inlet manifold incorporated the valley cover and interchangeable heads among other things. These features continued as the engine evolved over time to 350 cubic inches and finally 400. The all new design of the 55 Chevy didn't hurt acceptance of the new engine and the 55, 56 and 57 Chevys are some of the most popular and collectible 50s automobiles. Today it is possible to build a little Chevy without any original parts with a proliferation of aftermarket blocks, heads, manifolds and valve train components etc. I have such an engine in my 1956 coupe making over 600 reliable hp which your nanna could drive to the shops. The fundamental rightness of the design has withstood the test of time on the land, in the water and even in the air.