60 miles per hour all day long

[J Franklin]

I would run it at 60 MPH if I could replace it for under $600 new!

[Fullraceflathead]

I Truly Wonder if Henry Ford is Smiling in his Grave over this Subject

[Kurt in NJ]

I have run 65 all day-- after running 55+ for 2 days, that was 25 years ago and I am still trying to break it--- full advance, closed gav got 23 mpg at 65

If you truly restore to original specifications you will find that most modifications are not needed

[H. L. Chauvin]

Never noticed this mentioned before; however, on a slightly different audible subject, any comments on:

While in a totally "unmodified" 1928 - 1931 Model A ...... while cruising at 65 mph, ... with windshield closed, windows rolled up ......... on a scale of 1 to 10 ...... what is the required volume setting inside this Model A for listening and enjoying classical music played on a portable 2017 CD player?

Just wondering about audible toleration for guys with good hearing after driving a totally "unmodified" Model A at 60 mph for ........ 8 hours .... could this be more effective than obtaining enemy military information with water-boarding?

[pooch]

Originally Posted by frank55a

Many have said the Model A design speed was based on the roads of the day. You need to read the attached article.

This 3 year old strictly stock tudor known as the Phoenix Flyer which had established the record from LA to Phoenix, returned 3 years later and after 64,000 miles to better the time by 2 hours and 24 minutes over one of the most grueling 892-mile speed tests in the west. The entire round trip of 892 miles from LA to Phoenix and back to LA over burning deserts sands and steep mountain passes was made by this 3 year old car at an incredible average speed of 61.03 MPH.
Further just prior to this LA to Phoenix run the PF ran 500 miles over Muroc dry lake at an average of 66.66 MPH.

I zoomed in on the text of this pic.

Ya gotta just love the bit in the second column that says......

THE MODEL A IS THE NEAREST THING TO THE RACING CAR THAT I KNOW .....

Still laffing at that one.... a stock A tudor!!!!!

[40 Deluxe]

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Originally Posted by pooch

I zoomed in on the text of this pic.

Ya gotta just love the bit in the second column that says......

THE MODEL A IS THE NEAREST THING TO THE RACING CAR THAT I KNOW .....

Still laffing at that one.... a stock A tudor!!!!!

Well, the professional rebuilders on this forum say that the factory specs for an A engine are the same as modern race engine specs, so maybe the guy was right!

[BN]

Several posts in this thread have eluded to Ford's close machining tolerances and weight tolerances resulting in well balanced low vibration running engines. I have not seen any posts discussing the 2 per Rev (vibration frequency of 2 x RPM) which is inherent in any inline 4 cylinder engine. This 2 per Rev vibration is often called “secondary vibration” whereas 1 per Rev vibration is often called “primary vibration”. Modern 4 cylinder engines get around this 2 per Rev vibration problem by implementing an eccentric weight rotating 2 x engine speed. This 2 per Rev vibration is caused by the acceleration required to reverse the direction of the piston/rod assembly being different at TDC than at BDC. This is due to the difference in the angle between the crank pin and rod at, say, 5 Deg from TDC verses 5 Deg from BDC. This 2 per Rev vibration becomes stronger with longer connecting rods (as in a Model A engine). In addition, the two center pistons move together and the two end pistons move together in order to prevent a terrible rocking vibration. However, this results in an up/down vibration twice as severe. The engine in my 1929 Roadster was machined by a local well known reputable antique engine builder and included a counter weighted crank and a balance job. The car runs smoothly up to about 40 MPH, but then a vibration starts coming on at higher speeds and is much worse at 55 MPH. It is clearly a 2 per Rev vibration. I have never had the car above 55. It appears that Henry Ford was not oblivious to this 2 per Rev vibration problem. He took out a patent for a “vibration tuner” that diminishes this vibration somewhat which fit inside the oil pan. A “vibration tuner” is a small mass (of specified value) connected to a vibrating large mass (the engine block) by a spring (of specified value). I have often wondered if Ford went from the solid front motor mount to one with springs in an effort to reduce this 2 per Rev vibration.

[40 Deluxe]

Originally Posted by BN

It appears that Henry Ford was not oblivious to this 2 per Rev vibration problem. He took out a patent for a “vibration tuner” that diminishes this vibration somewhat which fit inside the oil pan. A “vibration tuner” is a small mass (of specified value) connected to a vibrating large mass (the engine block) by a spring (of specified value).

Is this the real reason the oil pump is held in with a spring?!

[BN]

Is this the real reason the oil pump is held in with a spring?!

Interesting thought. Did the early V8s (which did not have the 2 per Rev vibration problem) have spring mounted oil pumps?

[RawhideKid]

If I remember my early V8's, the oil pump was held in with a bolt to the bottom of the block.

[Kevin in NJ]

Originally Posted by BN

The engine in my 1929 Roadster was machined by a local well known reputable antique engine builder and included a counter weighted crank and a balance job.

Local well known reputable builder does not say much. Putting an engine together that sort of runs well up to 45 is not hard and you do not have to pay attention to much detail.

I quickly will start asking questions.

How was the crank ground? Was it checked for accuracy after grinding? Is the flywheel less then .001" from the center line? Are all the center lines the same?

What about the rods? Ford spec was a certain weight +- 1 gram at each end. Today most rods are +-5 grams total weight.

The rod/piston assembly was within 4grams in an engine.

Is your rebuilder aware of these specs? Can he build to these specs?

There are many variables that need to be considered when rebuilding the engine. I have been told by some rebuilders that Ford never built to those specs so why should they.

It is not easy, cheap or quick to properly rebuild the A. You have to ask lots of questions and know the answers. I have had access to Ford prints to know how many areas of the A were built at the factory so I know what it is supposed to be. Does your rebuilder know? Could he build to factory specs? Has he done tests of his work to be sure he can repeatably get the same accuracy in a build?

There is a reason why some cars have no trouble going over 55 MPH. There is also a reason why most do not.

[H. L. Chauvin]

At first decided not to tell my very recent 60 MPH experience and True Story; but so what ... here goes:

My wife and I, on a back road, drove a short distance, maybe one (1) mile, at 60 MPH the Saturday of the past weekend of the 4th of July in my 1930 Town Sedan.

I have a balanced Ron Kelley counter-weighted crank with his lightened balanced flywheel; (4) Coker 550-19" "Radial" tires; Police hi-compression head; Stipe 330 cam; B carburetor and B distributor; 3:27 differential ........... so in no way will I even attempt to try to convince anyone that this is an "original" Model A engine like that which I have in my 1930 Coupe.

At 60. still had space between accelerator and floor board; however, I have never tried to exceed 60 MPH in this car .... yet.

I usually average about 50 MPH when no rural traffic is around and no residences and no rural businesses are in sight; so at first I felt somewhat safe at 60 MPH with nobody behind me, no oncoming traffic, and just woods on both sides of this remote highway.

Then I thought about what if a deer crossed the road right in front of me like with my modern car a few years back, so I slowed back down to 50 MPH.

About five (5) minutes later, something rather startling ....... with no traffic, about 50 yards in front of me, a huge six (6) foot long alligator rapidly dashed across the road.

I then slowed down to about 20 MPH ....... then for a moment I couldn't remember off hand when was alligator mating season just in case this first alligator may have been a female.

Started laughing in thinking maybe a worse case Model A scenario may be to hit an alligator in the middle of nowhere, swerve to one side, get thrown out of a Model A, and have to fight a mean retaliating alligator with a Model A crank while my wife is trying to dial 911.

[Mike V. Florida]

The problem with this thread is the "... all day long" part. Even before I put the HC head on my car I did drive on the turnpike to shows early Sunday mornings and I did hit 60 for stretches but not all day long. I still have the engine and it still runs fine. Does this prove anything? I don't think so since I did not drive it all day that way.