When a site/blog re-design means a change in content

[2tails]

I want to use an old blog for something other than what it was originally used for. That would mean removing all the posts (perhaps) that are there now. This includes quite a few too.

My concerns are this...

What would that do to me in the search engines?

Of course that would mean all content that was once searchable would now result in 404's.

Or would one need to redirect everything in some way?

Lots of issues about this, I'm sure. Anyone done this before?

[Hiops]

Because you completely change your content it will be considered sa new website by SE. And I think the best you can do is 301 redirects from old pages ti the new ones. It probably something else should be done.

[2tails]

I would certainly hate to move all those posts (reviews) to another place and send redirects for them all.

[incrediblehelp]

Well will the new content match the old? If not why worry about 301 redirects? 404ing them is the best thing to do since this type of content doesn't exist anymore.

[2tails]

That is what I did. I just wiped it clean and stared over without worrying about the old content.