Here’s something you might not know

[blown motor]

Interesting.

[BIGSHCLUNK]

Murray, never heard of that before.......     

[JH27N0B]

As a pilot that doesn't make any sense to me, the big vertical stabilizer on an airplane makes the plane try to weathervane during ground operations in crosswinds, and we must counteract that from occurring using the rudder and ailerons, along with nose wheel steering on tricycle gear aircraft.

[blown motor]

I'm no engineer but the vertical stabilizer rises well above the body of the airplane and is flat so it would not deflect air like the rounded fuselage. The car is flat front and back so the side pressure would be more even.  Haha, look at me trying to rationalize aeronautical engineering! I'd be better off drinking, oh wait...

[JH27N0B]

There's a lot of physics involved and certainly the wings also contribute a lot to an airplane's tendencies toward weathervaning in crosswinds, but still how much additional steering effort have you had to exert when driving any car in a crosswind? I've never noticed it. Unless you are towing a trailer or driving a box truck or semi you probably haven't either.
Sounds like marketing BS to try to sell styling trends of the time as actually having a practical use.
Don't get me wrong, the fins styling trend of the late 50s did make for some cool looking cars!

[tparker]

I kinda agree it's marketing BS. Cool though. If it really worked and really mattered, we would have wings on todays cars. I don't think those cars were capable of speeds or cornering that would require wings, assuming they actually worked. But then again, I am no engineer and would be better off drinking too. LOL

[torredcuda]

I would think a car and plane are too different to compare aerodynamics - cars steer with the front wheels in contact with the road, planes use wings and flaps. Look at any race car and you will find lot`s of foils, spiolers etc. to help direct air flow and the Daytona and Superbird wings were wind tunnel tested to prove they worked but most are only effective over 100mph so not really a big factor for a street car.

[dodj]

I don't know if that's made up or not, (probably made up on FB) but I'm willing to bet they were just styling and not wind tunnel aerodynamics.
End plates on a wing prevent 'spillage' so to speak to help with downforce. Look at F1 and indy front car wings and you will see what I mean. You will see similar things on 737's and other planes.
BUT, I'm willing to bet the styling engineers of the day had no idea what the aerodynamic effect of those fins was.

[70 Top Banana]

That must have been put together in Chrysler's ( Plymouth) marketing department!

[Bullitt-]

      Appears they were at least trying to prove their design   

  about half way down....
https://www.allpar.com/threads/styling-fins-and-aerodynamics-virgil-exners-1957-report-and-the-dart-concept-car.227882/

[tparker]

A 1960 Plymouth Belvedere top speed is just over 100mph apparently. The average car on todays freeways cruise at about 80-85mph where I live. Not too many modern cars have a spoiler let alone vertical tail fins, and they handle just fine. Apparently physics changed in 1960 and aerodynamics didn't require tail fins for handling any more. I think it was a much more of a styling thing.