How to turn a grey authority-site into a white one?

Hi all!

I have a problem.
Have an authority-site for a certain keyword in the shopping-area.
the site is about 1 year old and has 200.000 sites indexed.
it was one of my first sites and to this time, i knew nothing about seo.
the site ist mostly created dynamicly out of csv-product-lists and it has nearly no unique content.
like i told you, it became an authority site, what i didnt expect.
that means (lets say e.g authority for "cars") when someone searches for cars, blue cars, big cars, cheap cars.... my site is one of the top 5, mostly on first place (by a result number of approximately 2.000.000)- thats why i think its an azthority

I make a good living out of this site, but as you know with a "grey" site it may not be listed in google for a long time.

Thats why I want to redo the site and make it a "white authority".

do you think this is possible?
What would be the right way?
turn down all content and set up a completely new site in one time?
can i put the site in a subfolder and do a 301-redirect to this subfolder, while doing up a new, clean site in the root?

hey guys, i dont want to loose all the traffic at once.
is there a way to make the grey site white without loosing ALL the traffic and (whats more important) without loosing the authority status?

thank you all for listening,
and soory for ma bad english.

MrAuthority

 

Google is punishing for duplicate content. You may want to make sure your content is original.

 

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