I want to say Liphistius malayanus gets a good size (~3.5' legspan or more). The one I have is only a 2" legspan.
I saw that you posted twice asking if anyone knew anything about trapdoors...
HAVE YOU TRIED SEARCHING THESE FOURMS? There are 2 trapdoor posts on the 1st page of the true spider fourm (just a few posts below yours). I use the search engine almost daily on these fourms... I'm sure you'll find a ton of info with alittle effort.
Just out of curiosity I searched the True Spider fourm for the keyword 'Trapdoor".... NINE PAGES of posts popped up reguarding trapdoor spiders...The info is here for you and I'm sure that any questions that aren't answered in the 9 pages of posted information could be answered if a specific question was posted.