1977 Ford Pinto counter wieght

the counterweight hanging off the back of the transmission, is design to reduce vibration of the driveline
that was one of Ford's better ideas, you better keep it on. I had a 77 Ford Pinto, I pulled the four cylinder out of the drop of 302 in it, then I took it to the street races in California of course it looked all stock with the 13" wheels I could not stop spinning unless I backed out of it and blew everyone's doors off. I'm jealous You have one still .