What about a system where other posters can give u points for a good post, thats relevant etc
And the rank is based off points.
That encourages good posters, and ppl who abuse the system can get banned.
I run an SMF forum as well, same software as this. What you're asking for isn't supported by the software and could cost upwards of around 60$ for a mod even. There is however a 'karma' feature, this can be activated in the main portal settings which gives the ability for everyone to give others a Like or Down vote for reputation type of system, similar to reddit.
To my knowledge, this can't be linked unless a modification for the forum software is created.