Probably due to limited keywords (realistic, online, racing simulation) and the main page layout isn't really designed for search engines (lacking header tags and informative paragraphs etc).
What would probably help would be a paragraph or 2 explaining briefly about LFS separate to the (cool concept, but annoying in reality) slidey-down-bit rather than just progress report snippets (or there abouts).
Tbh, I think the main LFS site really needs to be redone. It was brought up back when it was first publicised IIRC, but there's a few things I'd change personally for familiarity / user-friendliness alongside some SEO.