A used DeSoto 1955 in Belgium.

[Eve]

In 1955 my father bought a used DeSoto : see invoice attached.

Since the document is in dutch, I give You the translation.

 

Merk = Make

Type = Type

Kleur = Color

N° moteur = Motor number

N° chassis = Chassis number

Uitboring = Bore

Slaglengte = Stroke

Cylinders = Cylinders

Cyl. Inhoud = Cylinder capacity

HP = Tax class

Gewicht = Weight

Banden = Tyres

 

There are 2 odd things about this DeSoto.

The first is rather well known and good decribed in the history of the DeSoto brand.

The second odd thing is not at all common knowledge : I never found a word about it on the internet.

 

Can You figure out this two things?

Much pleasure searching !

 

Kind regards, Erik.

Antwerp, Belgium.

[Bloo]

6 cylinders and 2.83 liters?

 

Was that a Perkins diesel?

 

https://www.allpar.com/mopar/perkins.html

 

[Eve]

It was no diesel !

But You are hot.

 

Erik

[paul55]

I believe that the Diplomat model was for export only and may have had Dodge components (ie L-head 6 cylinder engine).

 

[Bloo]

Or Plymouth. Some had Plymouth bodies. 2.83 liters though is about 172 ci. Ever heard of a Dodge or Plymouth 6 that small?

[Harold]

The engine number on the invoice begins with 'SP23', and '51-'52 Plymouths had engine numbers beginning with 'P23'.  Makes me wonder if the car is a '51 Plymouth-based export DeSoto 

[Eve]

Yes, You are on the right way.

P23 12.714.521 identifies him as a '51 - '52 Plymouth Cranbrook built in Detroit.

 

The leading S makes him a "PlySoto" : equipped with a DeSoto grille and other ornaments.

The PlySoto's grille had 7 teeth, a regular DeSoto's had 9 teeth.

 

It was a 1951 model.

On my first driving lesson given me by my father, I stalled the motor releasing the clutch.

My father shouted :  "HANDBRAKE !!!".

Then I released the handbrake by the chromed handle.

1952 models had a plastic break handle.

 

So the first thing has been cleared.

 

For the second thing : this PlySoto left Detroit with a 3.6 liter flathead line 6...

- to be continued -

Erik

Edited October 14, 2019 by Eve (see edit history)

[Eve]

The government yearly imposes taxes on all vehicles driving on the national roads.

They fabricated a formula based on the weight of the car and the cylinder capacity of the motor.

So the "PlySoto" with the 3.6 liter engine was calculated as a HP 18.

This was rather expensive for the owner and a drawback selling the cars.

 

At that time my father was employed at Chrysler Antwerp as a "crankshaft and gears"-specialist.

Replacing the crankshaft and thus reducing the stroke the cylinder capacity was brought to 2.8 liter.

Horsepower felt from 98 to 76 HP. And the mileage on gasoline was better.

The cars now could be sold as HP 15, much more favorable taken in account that the scaling of the tax classes was not linear but rather exponential.

 

Needless to say that this cars were not racing horses. But that never was the purpose.

 

I nowhere found any notations about this practice in the company history.

If You have any more questions about this facts, I will try to answer.

 

Erik

[Harold]

Was the crankshaft exchange done to cars that were already built or a factory modification during production?

 

[Eve]

The crankshaft exchange was done to cars that were already built and imported.

The buyer was offered the choice : 18 or 15 HP. The conversion on stock cars did not take days...

 

Erik

[Rusty_OToole]

Chrysler often changed the displacement of their six cylinder engines by changing the stroke of the crankshaft. With different length connecting rods so the same pistons could be used. The longer the stroke, the shorter the rod. In this way they made 201 - 217 - and 230 cu in versions of the Plymouth/Dodge engine. I wonder if the conversion used different pistons or longer rods?

Edited October 15, 2019 by Rusty_OToole (see edit history)

[Eve]

Same pistons, other rods.

Edited October 16, 2019 by Eve (see edit history)

[Eve]

2.83 liter = 173 cu.