Video: 1948 Tucker Dyno Test

Much of the Tucker story is shrouded in myth and mystery, but thanks to Ida Automotive and Preston Tucker LLC,  one data point is now nailed down for good. Here’s a dyno test of an original Tucker 48. 

 

 

Preston Tucker made a number of ambitious claims about his Tucker 48 automobile, including its performance. After a radical 589 CID engine of the company’s own design failed to pan out, Tucker adapted the tried-and-tested Franklin 0-335 aircraft unit to the project, adding water cooling and automotive fuel and ignition systems for highway use. With a bore of 4.5 inches and a stroke of 3.5 inches, the big 335 CID flat six was rated at 160 horsepower—which would have made the Tucker one of the most powerful American cars on the road in 1948. At the time, Buick was rated at 148 hp, Cadillac at 150 hp, Packard at 160 hp.

To separate the facts from the salesmanship, Ida Automotive and Preston Tucker LLC recently sent Tucker no. 1044 to the chassis dyno. The famed Ohio barn find Tucker with only 8,000 miles showing on the odometer, no. 44 is said by Tucker experts to be probably the most original and authentic Tucker in existence.

Now, as Rob Ida notes in the video, there is a considerable difference between flywheel horsepower, as in the Tucker factory rating, and wheel horsepower as measured by the chassis dynamometer.  As he says, 20 percent may be a rough but useful rule of thumb for the mechanical losses eaten up by the drivetrain. Also, there are differences in air correction factors and fuels, and also in gross vs. net dyno testing methods, that surely come into play here. And it should probably be mentioned that while the test Tucker has only 8,000 miles, the engine is still 70 years old and in far from optimal testing condition.

So let’s cut to the bottom line. With no tuning or preparation at all, the barn find Tucker was simply driven up onto the dyno rollers, where it produced 221 lb-ft of torque and 90 peak horsepower at the rear wheels. That would make the Tucker factory rating of 160 gross flywheel horsepower more than plausible. Reasonable, even. Video below.

 

8 thoughts on “Video: 1948 Tucker Dyno Test

  1. Agreed, 160 hp is perfectly reasonable. In aircraft trim the engine produced 166 hp under very strict military standards. I bet the rings in the old engine are just about dead.

  2. Years ago we put my 1910 Ford Model T on a chassis dyno…….9 hp was achieved at the rear wheels from a car which was advertised as 20 hp when new!

    • Thanks for the info. This does not surprise me. A Model T can have an awful lot wrong with it and still run quite respectably, which is the beauty of them. Also, you may find this interesting: A few years back I ran a batch of Model T camshafts through the cam profile analyzer. They were all over the place, to the point it was difficult to know what was nominal.

  3. The Article above said Buick had a 148 H.P. rating, A Roadmaster has 150 H.P. Rating for those that are counting.
    Tucker specifications;
    Tucker 48, model year 1948, version for North America U.S.
    4-door sedan body type
    RWD (rear-wheel drive), manual 4-speed gearbox
    petrol (gasoline) engine with displacement: 5473 cm3 / 334 cui, advertised power: 124 kW / 166 hp / 169 PS ( SAE ), torque: 504 Nm / 372 lb-ft
    characteristic dimensions: outside length: 5563 mm / 219 in, width: 2007 mm / 79 in, wheelbase: 3302 mm / 130 in
    reference weights: base curb weight: 1921 kg / 4235 lbs

  4. IF they did not touch it that is very good. Simple stuff like timing and air fuel adjustments [jetting] may well have made a good deal more. Or maybe not. Though the torque figure would have been nice as they are a torque monster.

    • According to IDA this is what it put out;

      The car has a powerful but reserved thrum to it. Its engine was originally designed for a Bell helicopter, a flat-six Franklin. Tucker’s version of it was 5.5 liters and water-cooled, aiming for low-end power, with a spectacularly low redline.
      And that’s exactly what’s confirmed in this dyno run. The 44th Tucker put down 94 horsepower and 221 ft-lbs of torque at 2,700 RPM.

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