Maybe because I was only a kid when this was shown on CityTV's blue movie (snuck downstairs to watch) but "Carnal Knowledge" had a few scenes which made a big impression on my memory. Might not be what you're looking for but for the time, the movie was quite explicit - but tame by today's standards. The scene where Jack Nicholson is fucking Ann Margaret was pretty sexy (and you see Margaret naked for about 3 seconds!! - that was big stuff back then). The scene was mostly heard not seen, with a long panning shot leading to the bedroom as you hear Ann Margaret approaching climax. Nicholson had the best punchline for the scene: "I almost came that time.." The other scene was when Nicholson (who plays a dysfunctional asshole in the movie) takes Candice Bergen's virginity, even though his best friend (played by Art Garfunkle) was pursuing her. Bergen is a virginal, sweet character with Garfunkle so of course Nicholson lusts for her and pounces and takes advantage of her bad side. Oh, it has a great call-girl scene at the end too - again with the dysfunctional Nicholson still trying to get off (Rita Moreno plays the escort).