Some really good mentions in here already. You want funk then get some Ohio Players in your life my brother.
One of the funkiest concert albums I have heard in my life is James Brown's Love Power Peace from Paris in 1971. I received it as a Christmas gift a few years ago actually. I can't wait to blast this record on my Bose system. James and his crew (featuring Maceo Parker and Bootsy Collins) as tight as ever. The band is blazin hot. I would also recommend The JB's double CD anthology "Funky Good Time" which is a collection songs from James Brown and his best band which was the late 60s-early 70s period that featured Maceo, Bootsy & Catfish Collins, Fred Wesley, etc. You will likely hear some familiar tunes that were later sampled in hip hop tracks.