[rheltzel]

30-9, I think the old owner of your car was being hopelessly conservative. I routinely drove my '37 pickup which had a 3.78 rear end at 65 - 70 all day long. I must not have hurt it, as it was still going strong when I sold it, after putting 75,000 miles on the engine. I now have a '35 with its original engine (rebuilt about 8,000 miles ago) and I drive it at 60 to 65 almost every day. If your rear end isn't making any funny noises, I wouldn't hesitate to drive it at faster speeds. As to the engine, if it's otherwise sound, i.e., doesn't overheat, isn't making any terminal death noises (e.g. knocking bearings), I wouldn't hesitate to drive it continuously at 60 - 65. Flathead Ford V8's were (and still are) extremely robust engines.