Best or favorite? Not gonna do best because it would be another source of online arguments....
But my favorite well, that would be based on the most fun to drive or had fun in. My first car was a 69 Dart with a 318 and some stuff done and it ran pretty good relatively speaking for the mid '80s, had a lot of fun in that. My 94 Caprice, loaded with leather, light blue with an LT1, 3.73 gears, headers, cat deleted, intake, 1.6 rockers...ran real good for the mid late 90's, a real sleeper. Then my 07 TBSS, with just my homemade intake, and tune, ud pulley, t-stat ran 13.08, not as much of a sleeper, but it surprised a lot of people. All I had alot of fun in.