What is a "reasonable" speed in a Model A for one to get "reasonable" engine life?

[Synchro909]

Before I installed an O/D, I used to sit the car on 42mph, never more. Both the car and I were happy at that and I did many thousands of miles that way. Since the O/D went in, I drive at 50mph which is slightly lower revs than before and the car is even happier so I am too. We can even talk to each other now as we go. Things are much quieter even though we are going faster.

[Robert/Texas]

Back in the 1950’s I bought a ’28 roadster from the granddaughter of the original owner for $100. It was stock except for 1932 wheels. I drove this car hard for a couple of years and one day I decided to see how fast it would go. It got up to about 65 and threw a rod through the oil pan, damaging the block. Rebuilt Model A short blocks were selling at Sears for $35 without exchange so I scrounged up the money and went there. This was my lucky day. Sears was selling out all their Model A stuff and short blocks were $5. They had three and the manager wanted me to take them all, but I only bought one. He gave me a free after-market carburetor and distributor to boot.

On the next Saturday two friends and I pulled the engine using a 2x4 and rope. We transferred everything from the old engine to the Sears one and reinstalled the engine in the same day. I never used the other parts that Sears gave me.

I drove the car for another year or so without any problems and then sold it to a younger guy. He had a Riley head that he was going to use on it and had cut down {instead of removing), all four fenders. The next time I went to see him he had joined the Navy.

A sad ending for this car, I never found out what happened to it after that. I got another ’28 roadster in 1989, rebuilt the engine some years ago and still have it. I never drive it over 45 MPH.

Robert

[Gene F]

Sometimes a rebuild is not needed. Sometimes all that is needed is a fresh head gasket.

[Curt phillips]

Just purchased a 29 Tudor & have never drove or rode in a model A !
What a experience, steers ok stops good runs great. Got up to 55 twice
On a long empty road and it would go faster. I wouldn’t do that again after
Telling a guy that has a model A about doing that & he said if ya hit a big
Enough hole in the road ya might have to choose if ya going with the frame
Or the body! What gets me is how many cars will pull out in front or me in
Just the 2 months I been driving it! 40 to 45 max for me.

[WHN]

Everything working right, 35 to 40 MPH, car loves it. On up to 45 MPH, car doesn’t mind but starting to breath heavy. Over 45 MPH, you can feel it starting to work. Over 50 MPH, we are both to old!

Enjoy

[40 Deluxe]

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Originally Posted by Curt phillips

Just purchased a 29 Tudor & have never drove or rode in a model A !
What a experience, steers ok stops good runs great. Got up to 55 twice
On a long empty road and it would go faster. I wouldn’t do that again after
Telling a guy that has a model A about doing that & he said if ya hit a big
Enough hole in the road ya might have to choose if ya going with the frame
Or the body! What gets me is how many cars will pull out in front or me in
Just the 2 months I been driving it! 40 to 45 max for me.

So how many documented cases are there of a body separating from the frame after hitting a pothole? Does anyone have pictures?

[Jack Shaft]

I chickened out at 80 with mine,she'll do 62 right comfortable,A engine (modified) mitchell OD..

Id like to see that too,a body being violently removed from the frame I'd say its impossible if all the mount bolts were used.

[Bill G]

Me? 45, sometimes 50 with standard tranny and no OD.

[Curt phillips]

Oh I don’t think that would happen but it was enough to slow me
Down, and with no seat belts & a tank of gas in my lap I’ll hold
Down the rear

[eagle]

Listen to your car. Mine runs easy at 45 to just under 50. Over 50 its starting to feel a bit frantic. Getting close to 60, she's in adrenalin mode. Why not stay in the sweet spot? Ive got lots of country roads all to myself, and I drive my A for enjoyment.

[1928Mik]

I'm with 'eagle' on all counts!

[Bob Bidonde]

Been cruising at 50 to 60 MPH with Model "A" and Model "B" engines on highways with babbitt bearings, 3.78 differential and no overdrive since 1962. No engine failures yet. Slow speeds are unsafe in modern traffic!

The only engine failure I personally experienced was with a freshly rebuilt Model "A" engine. Investigation revealed that the re-builder tied the oil pump into place with a piece of clothesline. The clothesline disintegrated and clogged the oil pump screen. Since then, I never trust an engine re-builder, so I take apart every rebuilt engine. None have been without faults, thankfully minor ones.

[Bob Bidonde]

Been driving 50 to 60 MPH with Model "A" and Model "B" engines on highways with babbitt bearings, 3.78 differential and no overdrive since 1962. No engine failures yet. Slow speeds are unsafe in modern traffic!

The only engine failure I personally experienced was with a freshly rebuilt Model "A" engine. Investigation revealed that the re-builder tied the oil pump into place with a piece of clothesline. The clothesline disintegrated and clogged the oil pump screen. Since then, I never trust an engine re-builder, so I take apart every rebuilt engine. None have been without faults, thankfully minor ones.

[nkaminar]

My just purchased engine has insert bearings and a counterbalanced crank. This is my 6th Model A (all the others were sold, damnit). All the stock ones I drove at 50 or so. This one will go 70 or more and the vibration is low. It is a 1930 Fordor and has an overdrive. I plan to drive it on back roads at 55 or so. What does the group have to say about this?

[JD 1931]

45-50 mph top no mountains here

[Kurt in NJ]

Originally Posted by Bob Bidonde

Been driving 50 to 60 MPH with Model "A" and Model "B" engines on highways with babbitt bearings, 3.78 differential and no overdrive since 1962. No engine failures yet. Slow speeds are unsafe in modern traffic!

The only engine failure I personally experienced was with a freshly rebuilt Model "A" engine. Investigation revealed that the re-builder tied the oil pump into place with a piece of clothesline. The clothesline disintegrated and clogged the oil pump screen. Since then, I never trust an engine re-builder, so I take apart every rebuilt engine. None have been without faults, thankfully minor ones.

After I had the rear main failure I got to look at 2 other engines rebuilt by the same place, neither had been run, one still had wadding in the oil passages to the mains, the other one the oil holes hadn't even been drilled

[Gene F]

Originally Posted by Curt phillips

Just purchased a 29 Tudor & have never drove or rode in a model A !
What a experience, steers ok stops good runs great. Got up to 55 twice
On a long empty road and it would go faster. I wouldn’t do that again after
Telling a guy that has a model A about doing that & he said if ya hit a big
Enough hole in the road ya might have to choose if ya going with the frame
Or the body! What gets me is how many cars will pull out in front or me in
Just the 2 months I been driving it! 40 to 45 max for me.

Curt, you are correct.. My wife sometimes drive our streetrod, and she notices the same thing. People think that they don't want to "get caught behind that old car". In the case of the streetrod, what they don't understand is that old car can often move faster than they can.

[Gene F]

Originally Posted by Kurt in NJ

After I had the rear main failure I got to look at 2 other engines rebuilt by the same place, neither had been run, one still had wadding in the oil passages to the mains, the other one the oil holes hadn't even been drilled

It's amazing isn't it! Years ago we had a guy in our club took his car out with a fresh engine, installed in a shop. Drove it some, and next thing ya know it had to be towed in. Someone forgot to put cotter pins in the rod caps. TORE IT UP!

And if ya say anything the supposed engine rebuilders get mad...

[bdtutton]

I have a 1930 Tudor and it is happy at 45-52 all day long. It will run up to 60 fairly easy, but you can tell it is unhappy spinning that fast. I plan to add an overdrive, but I plan to rebuild the brakes with new cast iron drums first. You need to be able to stop before you think about going fast.

[Jack Shaft]

Originally Posted by Gene F

It's amazing isn't it! Years ago we had a guy in our club took his car out with a fresh engine, installed in a shop. Drove it some, and next thing ya know it had to be towed in. Someone forgot to put cotter pins in the rod caps. TORE IT UP!

And if ya say anything the supposed engine rebuilders get mad...

I yell at my engine builder every morning in the mirror when I shave ..do your own work,you'll have no one to be mad at..


The sweet spot folks describe on here is important to understand,its natures way of telling you your exceeding the limits of harmonic and torsional vibration that occurs with a stock model a crankshaft,the late Herm Kohnke maintained a model a crankshaft will flex at the center bearing .001 when vibrating hard ( picture a tuning fork) pay heed to that uncomfortable feeling you get,you'll save your main bearings..