…would definitely be John Holmes
I quote from http://listverse.com/
One of the most prolific male porn stars of all time, John Holmes starred in approximately 2,500 films, from loops to features, in the ‘70s and ‘80s, and is estimated to have had sex with about 3,000 women (and several men). Known mostly for his large penis, Holmes later gained notoriety for his involvement in a drug related shooting in LA. Born in Ohio in 1944, Holmes kicked around most of his teenage life due to problems at home. He joined the army, and later married. He was “discovered” by a photographer, who saw Holmes’ impressive member at a urinal, and encouraged him to get into porn. Holmes’ quickly became the King of Porn, and starred in a series of hardcore films as detective “Johnny Wadd.” He made dozens of films during this time, making lots of money and taking part in the excesses of fame, such as drugs and partying.
By the early ‘80s, a severe cocaine addiction had taken its toll. He wasn’t able to “perform” as well as he used to. Desperate for money and drugs, Holmes began prostituting himself and his new young girlfriend to men and women. He became involved in drug trafficking with various gangs, and was arrested for his alleged involvement in the murder of four drug dealers on Wonderland Avenue, in Laurel Canyon. He was later released due to lack of evidence. Holmes was diagnosed with AIDS in 1986, probably from having sex with an HIV-positive man on film in the early ‘80s. (Holmes never used needles for drugs.) He died from complications of the disease in 1988.