road speed question

[Standing Elk]

What is a good comfortable highway cruising speed for a Model A car. Would a steady diet of 45-55 MPH be working the engine too much? I have a 24 TT now and am thinking about getting a Model A car for some longer trips. Just curious. Thanks

[Charlie Stephens]

I have a '31 RDPU with a 3.54 rear end. Light vehicle, high rear end. B engine with counterweighted crank. Shouldn't be that much different than a well built Model A engine. I am comfortable at 55 MPH. Above that the front fenders make the front end too light and it is subject to winds from passing trucks and winds blowing down canyons that cross the road.

Charlie Stephens

[daveymc29]

I have a roadster with Mitchell 26% OD, 3:54 rear end running 600 X 16 tires on the ground. Pulls the hills here in California fine and can drive 55 all day. Burst of 65 don't seem too bad but the car is too light for that speed. (For me.) I have a coupe, stock with 3:78 rear and 600 X 16's on the ground. 55 seems to be pushing it, though I have done it for a few miles I am uncomfortable with the high rpm. 47 seems a good speed with stock tires and 3:78 rear unless you have the OD of some sort. jmho

[Synchro909]

You're going to get a wide range of speeds in answer to your question. Drive it at whatever speed it (and you) are comfortable with.
That said, I don't like having the engine revving very highly but I cruise at anything between 80 and 95 kph with an overdrive fitted. If you want to cruise at these sorts of speeds, I suggest an O/D to give you basically 4 forward speeds (6 if you want). Others will suggest a higher ratio diff but I don't like the big gap between 2nd and third gears being accentuated by the high ratio rear end.
The beauty of these cars is that with a little works, you can get a lot more out of them without too much affecting reliability.
All just MHO.

[RawhideKid]

Originally Posted by Standing Elk

What is a good comfortable highway cruising speed for a Model A car. Would a steady diet of 45-55 MPH be working the engine too much? I have a 24 TT now and am thinking about getting a Model A car for some longer trips. Just curious. Thanks

Finding the "sweet spot" speed for any Model A is something that has to be done on an individual basis. If you are running the stock 3:78 rear end, I wouldn't rev too high for any length of time. If you have to go fast, you will have to modify the car with either a 3:27 rear end, or a late model OD trans or both. The stock engine is only good for about 2200rpm for an extended period of time unless that too is modified.

After running the TT getting into a model A is like going warp speed. If you need to sustain a speed of 45 to 50 where you live, unless you have a perfect running/cooling Model A, or modified drive train, something will need to give.

Just remember, you will not be able to drive faster than you feel you can safely stop!

[Patrick L.]

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A regular unmodified 'A' is a 40-45 mph vehicle.

Some will argue that statement though, but, most will agree.

[springerpete]

Whenever I see these speed questions I always am looking at the other end of the equation: what about stopping ? With really great mechanical brakes I've heard you can lock up call four wheels. Is that the norm for all Model A's ? I am much more concerned with escaping an accident with a child on a bike or an animal that runs out on the road. If 55 is your song why not use your daily driver ? 35 to 40 gives you a chance to enjoy the scenery, wave at the folks who wave to you and be safe.

[WHN]

Our 29 loves 40 mph, it will easily go faster but why.

All stock, everything rebuilt, drives great, it's our baby. I'm not looking to prove anything.

We have had this car for 40 years, I am getting to old to go through a rebuild.

[H. L. Chauvin]

Lots depends on what individual drivers may assume to be comfortable Model A speeds; and even though comfortable speeds vary with modern cars, many different mph answers depends sometimes on highway conditions and Model A capability.

For example:

1. Heavy traffic or light traffic?

2. Woods both sides of highway with few or lots of deer or Elk crossing? ... No pun intended.

3. Houses or businesses both sides of highway with half blind senior drivers and texting teenagers entering and existing driveways?

4. Smooth roads, rough roads; few stop signs/traffic lights or many of same?

5. Maybe a wild guess at a General Rule of Thumb for only "Highway Conditions" may be:

Comfortable Model A Speed = Comfortable Modern Car Speed minus (5) to (10) miles per hour.

[J Franklin]

A TT is much different than a T or A. I had a stock T roadster that went 45 easily. I was uncomfortable with the flimsy feeling steering even though all was tight. My A likes 40 to 50 MPH for cruising along. It is a 4 door with a brumfield head, b distributor, 19 in. wheels, good steering & 3:78 Diff., otherwise it is stock.

[glenn in camino]

I have 3 Model As that are totally stock that I drive at 45-50 mph on tours. My modified Model As(built up engines, overdrives etc.) run nicely at 55-60 on the freeway.

[H. L. Chauvin]

Not trying to start WW-III with Model A tire selections.

But, if you look under "Search" above, you can read about Model A Forum reports and comments on Model A's with 19" wheels, (i.e., later Model A Fords with wider tires), with newly installed 550-19 Coker "Radial" Tires in lieu of any other brand of 19" "Bias" tires.

If wanting to travel more frequently with more "comfort", comments can be found about quite a difference in better road handling and less wandering with the more "Radial" tire tread area in contact with the highway than that of "Bias" tires.

Just trying to comment on part of your initial question:

"What is a good "comfortable" highway cruising speed for a Model A car."

[CarlG]

Our target speed while touring is 50 - 55. Most are stock with 3:78 gears. Going solo I usually kick it up a bit to the 55 - 60 area. I do have the F150 overdrive and 550R19 tires. Speed is monitored by GPS.

[Kevin in NJ]

Contrary to common opinion, if the car is rebuilt to Factory specs you can expect a car capable of sustaned 60 MPH.
The car should be comfortable to run 50-55 MPH all day long. You are not hurting anything if the crank and rods were built to factory specs.
Yes, it will stop fine for something with the thin tires. The braking limits are the rubber on the road.

Quite often you will here tell of 40 to 45 MPH. Every car someone tells me is only good for those speeds I look at the mechanical condition of the car and doubt it is safe that fast. I guess I am picky.

[WHN]

Originally Posted by Kevin in NJ

Contrary to common opinion, if the car is rebuilt to Factory specs you can expect a car capable of sustaned 60 MPH.
The car should be comfortable to run 50-55 MPH all day long. You are not hurting anything if the crank and rods were built to factory specs.
Yes, it will stop fine for something with the thin tires. The braking limits are the rubber on the road.

Quite often you will here tell of 40 to 45 MPH. Every car someone tells me is only good for those speeds I look at the mechanical condition of the car and doubt it is safe that fast. I guess I am picky.

I would take exception to the "every car" comment. Some of us just love our cars and enjoy the old slow lane. Just because we drive under 45 does not mean our car is not as good or better than yours mechanically. We are just different. Enjoy.

[Synchro909]

I'm not worried about setting any speed records either. How often do we see the same car that took off from the last set of lights like a startled rabbit waiting for us at the next set of lights or in the next town?
I prefer to proceed with grace, not pace. (especially if Grace is a good looker!)

[Tom Wesenberg]

Originally Posted by Synchro909

I'm not worried about setting any speed records either. How often do we see the same car that took off from the last set of lights like a startled rabbit waiting for us at the next set of lights or in the next town?
I prefer to proceed with grace, not pace. (especially if Grace is a good looker!)

Good one!

Grace was my 10th grade biology partner, and she was a good looker.

[Smooth_One]

^ ha ha

[jim1932]

Keep in mind the question was about capability, not what speed are you comfortable at. Having tried to quickly stop a model B after running it up on a downhill. I agree the brakes limit more than the motor/gearing do.

[H. L. Chauvin]

With his two (2) initial questions:

A. "What is a good "comfortable" highway cruising speed for a Model A car.", and,

B. "Would a steady diet of 45-55 MPH be working the engine too much?"


1. Like with individual modern cars, no two (2) individual Model A's are exactly alike; and,

2. Like with individual modern drivers, no two (2) individual Model A drivers are exactly alike; and'

3. Like with individual modern highways, no two (2) individual Model A traveled highways are exactly alike; hence,

4. With just these few variables, it appears somewhat reasonable that a particular "comfortable" Model A speed is a variable speed where:

A particular Model A driver feels comfortable while driving a particular Model A on a particular highway.