"clones" "small block" "big block"?


What is a clone? Whats the difference betwenn a small block and big block engine, thought I knew until I heard a 427 being referred to as a small block. Thanks in advance.


A clone is a classic muscle car that was built up after the fact from a non-muscle car base model. As an example, a cloned 426 Hemi Challenger is typically cloned from a more readily available 318 Challenger, and then re-built to look like the legendary 426 Hemi version. The reason is, Chrysler only sold a limited number of the original 426 Hemis, with even fewer surviving today with an extremely large price tag. However, there are much more basic Challengers still around and could be bought cheap, and it is much cheaper to build a clone from the base model.

Small block and Big Block refer to the configuration of the engine block. A big block is just that, a much larger engine block that is typically designed for engine displacements from 350 cubic inches to 500 cubic inches and beyond. A small block is typically designed for displacements from 289 cubic inches to 350 cubic inches.

But the aftermarket continues to blurr the lines. I’ve seen a couple of custom engine shops that can build a 427 small block engine that can drop-in replace any chevy small block, and uses the same mounting points and accessory brackets. You cannot go by displacement alone to determine if small block or big block.