Re: Cruising speed

Posted by Packard Newbie On 2020/1/5 2:23:32

Cartrich, I just forget what year your car is, 36 or 37, right? I am presuming you have the same motor as my '39 Six (the '39's were not called 110's or 115's) which is the Packard 245 CID flathead. High revs are definitely the enemy of those motors and you can hear them when they rev too high. I find my six can highway-cruise comfortably at about 55. I sometimes hit 60 when going down a hill or passing (which takes a pretty slow vehicle!!) but I believe you would be doing the internals of the engine long term harm to push it any harder than that. It's worthy of mention that the car must be in good mechanical shape to GO on the highway in the first place, with good brakes, a safe front end and decent rubber, etc. The other option, of course, is to install an overdrive transmission, which is quite a project and expense, but the O/D is supposed to slow the RPM's down by about 27%, according to Packard literature. The same car in overdrive can probably cruise at 65/70, maybe even touching 75/80 once in a while, without harming the engine. Those experienced with overdrive will probably weigh in with some input, but, FWIW, that's my take on the question. Chris.