The Ford Barn - View Single Post - What is average highway speed for the model a?

Special Coupe Frank · 09-09-2010, 02:35 PM

I don't have a tach; those numbers were calculated from the mounted diameter of the tires / circumference, which in turn is calculated into "revolutions per mile", which is then calculated against the ring & pinion ratio to determine the "engine revolutions per mile", which in turn gives you your engine RPM at a given road-speed...

I'm not a math geek by any stretch, just plugged through the math one day, and came up with the numbers...

I certainly appreciate driving "by feel", and mostly do that myself, but I can tell you that a Model A with 21" or 19" tires and a 3.78 rear "sounds / feels" a LOT less "busy" at 50 mph than my friend's '40 Chevy six with 16" wheels and 4.11 rear at the same speed...

I like keeping my A under 50 MPH.

09-09-2010, 02:35 PM	#57
Special Coupe Frank Senior Member Join Date: May 2010 Location: Northeast Penna Posts: 2,108	Re: What is average highway speed for the model a? I don't have a tach; those numbers were calculated from the mounted diameter of the tires / circumference, which in turn is calculated into "revolutions per mile", which is then calculated against the ring & pinion ratio to determine the "engine revolutions per mile", which in turn gives you your engine RPM at a given road-speed... I'm not a math geek by any stretch, just plugged through the math one day, and came up with the numbers... I certainly appreciate driving "by feel", and mostly do that myself, but I can tell you that a Model A with 21" or 19" tires and a 3.78 rear "sounds / feels" a LOT less "busy" at 50 mph than my friend's '40 Chevy six with 16" wheels and 4.11 rear at the same speed... I like keeping my A under 50 MPH.