I have a phpbb-seo'd site and I want to split one of the forums into a new site.

My site has 3 forums: General Chat, Dating, Events.

Basicaly what I want to do is take all the threads from the Events forum and move it to a completely new site / domain.

I'm basically going to copy the database over to the new domain.

how do I set up redirection on the old site so that all the old google backlinks for the Events forum threads now point to the copied over threads in the new domain?

What I would do to make this simpler would be to turn the forum private and use a mod like nv newspage to display its content where you want.
This way you would still be able to post new content from phpBB directly and see them published there.
This would only require that you can set you other domain (or sub domain) within the same host as phpBB. You could also only make so the script can access the phpBB db remotly, but you would then need to mod it to run independently from phpBB or to add all the required phpBB files for it to run.

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