[red369]

Very interesting - I’ve always been confused by why aluminium is often stated as being rust-proof, but doesn’t appear to be as useful in the real world.

Aren’t there quite a few aluminium engine blocks in cars though? For example, the LS small block is now aluminium.

Or do you mean used in marine applications, where rust is an issue? That would probably make more sense (and may actually be implied by the context).