There are new signs on the outside of the officially renamed Daniel G. and Carole L. Kamin Science Center — and many more changes inside. The most visible change, from the science museum’s decades-old Carnegie Science Center moniker, is in honor of a massive, $65 million gift from Daniel G. and Carole L. Kamin, the largest in the history of the Carnegie Museums. Next summer, a new experience called the “Science of Speed” — housed in the former SportsWorks building — will focus on the science behind elite race cars. The “Science of Speed” building will also feature a restaurant and lounge which will remain open after museum hours. The Kamin Science Center will reopen its doors to the public on Saturday with its “(Re)Launch Day” celebration.