I think people are starting to get confused, and not reading the entire thread (rather just the OP's request)...
Bottom line:
IF we consider it, there will be a General NON-SR20 related subforum. This means, non-make/model/etc. specific. It will be general technical information that the OP of a thread will post on their particular vehicle.
I would envision it as our community helping each other with regards to our specific skill level, on other makes and models of vehicles. For instance, the '03 Bonneville thread I had started in O/T is technical in nature, not some O/T rambling. The current format of the O/T section allows for O/T rambling, in O/T threads. Many threads start as one item, and finish with something completely unrelated to the original topic. Kinda like the game of telephone we played in school, right?
If we create a general "mechanical" non-sr related section, this will help eliminate some of that O/T chatter so everyone gets to assist if they're knowledgeable on the particular subject the OP creates.
I do agree with everyone here (as I clearly stated "headache") if we go the way of autoforums by adding vehicle specific sections/subforums. That would tarnish the sites reputation for being small/compact/etc.
As an aside, to eliminate outsider influence on the specific section I'd have to say it be treated as O/T, in that it is not externally searchable by random passer's by.
In a nutshell? A few guys here have Subaru vehicles, or other Nissan vehicles with different motors. A thread on a timing belt replacement for an EJ wouldn't be a bad idea to help those that have Subaru boxer equipped cars which quite a few folks here have. That doesn't take away from the primary purpose of this community built forum which is just that... community.