No, vim is not multithreaded. Multiple cores won't help you here.
First we have to agree on what a huge file is. I suppose you mean a file larger than the RAM size. Vim was not designed for large files. Furthermore, when not sufficient line ends are present, vim might not be able to open the file at all.
Decide if you want to just read the file content or if you want to edit it. The program
less has many features unknown to most people and is actually a very good tool to view large files because it doesn't require the file to fit into memory.
If you want to edit the file you are better off with non-interactive text editors like
awk or maybe a
perl script. Those editors were designed for this very purpose and happily process files larger than your RAM.
Also see my answer to: What happens if I use vi on large files?