This is almost thrilling to hear about. I have a 1953 3600 with the granny 4 on the floor. torque tube etc. If changing out the gears in the pumpkin gets ya an additional 5 MPH what your RPMs? Mine is smooth on the hiway up to about 60 mph but I'm turning at 3100 to 3200 rpms. It works but I'm worried I'm pushing the 1959 235 motor too hard. . What kind or RPMs are my fellow 3600 owners turning with new rear ends?
