With a straight front axle I think 55 is fast enough and of course with drum brakes all around it can be fun. I was just wondering what these old engines were worked at RPM wise as they were farm tools. My Grandpa had a 48/3100 with 216 but he never went over 45 as a rule...not that I can remember. Now that I have an RPM gage I need to learn a set of new rules. T/C Steve, Steve