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

Kevin in NJ · 09-05-2010, 08:09 PM

It depends on a lot of factors.

The major factor is how well balanced all the parts are and how good is your cam.

I grew up thinking 55 to 60 was the normal speed as that is what my brothers 31 coupe was always driven (since 1970). My crappy looking fordor liked running those speeds too.

Ford spent a lot engineering to be able to do precision work on the all the critical parts. It was cheaper to build a car when any parts put together would result in a balanced engine.

Today is is VERY rare to find a crank grinder that can keep it all centered up. Throw in out of balance rods and pistons and a worn cam and it you get a pot luck engine. I know a bunch of cars near me where the guys drive 45 and I believe that is too fast for the cars.

If the car is built right you will not feel you are pushing it to run 55+. That is without any real major mods, just building the chassis back to factory. With modern fuel a slightly higher compression head and some B grind cam will keep the car pretty close to factory and get a bunch of extra power with out over doing it.

Keep in mind a balanced engine put very little load on the bearings if you are running the advance properly and keeping the rpms up. Lugging the engine is what is not good for the bearings. Just spinning along cruising down the highway the engine is a happy camper at 55+.

But what do I know?

09-05-2010, 08:09 PM	#5
Kevin in NJ Senior Member Join Date: May 2010 Location: South East NJ Posts: 3,398	Re: What is average highway speed for the model a? It depends on a lot of factors. The major factor is how well balanced all the parts are and how good is your cam. I grew up thinking 55 to 60 was the normal speed as that is what my brothers 31 coupe was always driven (since 1970). My crappy looking fordor liked running those speeds too. Ford spent a lot engineering to be able to do precision work on the all the critical parts. It was cheaper to build a car when any parts put together would result in a balanced engine. Today is is VERY rare to find a crank grinder that can keep it all centered up. Throw in out of balance rods and pistons and a worn cam and it you get a pot luck engine. I know a bunch of cars near me where the guys drive 45 and I believe that is too fast for the cars. If the car is built right you will not feel you are pushing it to run 55+. That is without any real major mods, just building the chassis back to factory. With modern fuel a slightly higher compression head and some B grind cam will keep the car pretty close to factory and get a bunch of extra power with out over doing it. Keep in mind a balanced engine put very little load on the bearings if you are running the advance properly and keeping the rpms up. Lugging the engine is what is not good for the bearings. Just spinning along cruising down the highway the engine is a happy camper at 55+. But what do I know?