Sadly the real solution would involve updating the software on the site to enhance the user signup page (even a simple 5 minute fix could possibly do it), and some of the passwords required to manage those systems are held by a single person (Vtac, the owner of this site). And he tends to go MIA for several months (years?) at a time.
That's why you'll note that FuckCombustion.com is not running on HTTPS, chrome and other browsers report this site is not secured. It's not expensive/difficult to implement the SSL needed to secure the site, but nobody else can do it. And so FC's listing rank on Google Search has fallen since the site is not secured and that negatively affects the site's SEO score.
We really don't give enough credit to the remaining admins who put in hard work daily to delete/block these spammers whenever they pop up.