The original Hawaii 5-0 featured numerous car chases and Ford-Lincoln-Mercury products and the first promo for the show indicates the new Hawaii 5-0 won't stray far from this formula. From the trailer it's clear the Mustang 5.0 belongs to the "Danno" character and carries 5.0 badges. The original "Danno" did drive a white Ford Mustang for some episodes. A spokesperson for Ford confirmed they're involved in the production of the show.
Whether or not this is an actual 5.0 is another story. The are rumors the car is actually a V6 model rebadged to look like 5.0 'Stang, possibly because a real 5.0 wasn't available when they shot the pilot. Either way, we're pro continuing the traditional look of the show instead of trying to force a Mustang where it doesn't belong.