I drove back in those days. It was simple. You kept it in a gear where you were turning about 4,000 RPM. We depended on RPM instead of torque back in those days. But we got the job done. This is why I think it is so stupid when I hear buys worrying about their engines coming apart at over 2500 RPM. I would have fired a driver for lugging an engine at 2500 RPM.
