Which car is better aerodynamically ?

[Daytona R/T SE]

Which car is better aerodynamically ?

The 1969 Dodge Charger 500,

Or...

The 1971/1972 Dodge Charger ?

     

For the sake of discussion, lets assume that both cars are stock, factory Hemi four speed cars.

Stock, right down to the tires.

Which one produces less drag, and cuts through the air better ?

Which one has the better down force at speed, and which one is trying to fly ?  
 


 

[Daytona Guy]

I heard the 71-72 had a better coefficiency number. But don't know for sure.

Dane   

[Aero426]

The answer may depend on at what stage of development of the third gen body you want to use.   They had essentially seven seasons on that car.  Later on, cars like Petty's Chargers were well sorted and massaged.   But if we are talking 71-72...

The G-series wind tunnel report states that the standard 1971 Dodge set up for racing was not as good as the preceding E-series (Charger 500) race cars in terms of having greater axial force and significantly more rear lift. So there is the basic answer.

[Aero426]

The grille of the 500 compared to the 71-72 would be pretty close. 
Windshield is a little more laid back on the 71-72.
The covered by the hood cowl of the 71-72 is a disadvantage compared to the way the engine takes it's air on the 500 with the open cowl panel.
Rear window of the 500 is a significant advantage.
The flatter sides of the 69 may be an advantage.   The 71-72 body is wider.

[Daytona R/T SE]

The G-series wind tunnel report states that the standard 1971 Dodge set up for racing was not as good as the preceding E-series (Charger 500) race cars in terms of having greater axial force and significantly more rear lift. So there is the basic answer.

Thanks, Doug !

[Mike DC]

The 3rd-gen windshield is more laidback but it's also wider/bigger overall and doesn't curve back as much at the sides.  In terms of aero it's probably a step backward from the 2nd-gen windshield.

[RallyeMike]

The stock 72 Hemi car is best in all categories because its mythical.

[odcics2]

Sticking with the OPs question, it's apples and oranges.
The few reasons above, both pro and con for each style do hold water.

Look at back in the day pics of production Hemi Charger 500s.  That nose was way up in the air, if the car was at proper curb height, as specified.

Now, the 71-72 Charger nose pierces the air much lower...     I would think we all agree that lower is better.

So, a high nosed fast back with good "A" pillar air flow, versus a laid back windshield, low nosed, poor "A" pillar style.

You'd have to do a wind tunnel study to know for sure...     

Comparing purpose built race cars, I'd give the nod to the '69 500.   


p.s. Talking to Gary Romberg in 1976, he told me that by 1974, Petty was getting laminar flow over the backlight at Daytona, using rake.
      This would cause the drag number to come down to '69 Charger 500 territory...   

[Daytona R/T SE]

The stock 72 Hemi car is best in all categories because its mythical.

Oops.

I had a brain fart last night.

Let's leave the mythical '72 Hemi cars out of it.

[Daytona Guy]

Can we compare speeds? How did the 72-72 fair with the 500's with 426's in them?

Dane

[odcics2]

How would you compensate for restrictor plates which were used beginning in August 1970 at the Yankee 400 at MIS?     

The 71-72 Chargers always had them on every track. That's when Nascar was playing around with hole sizes, almost on a weekly basis!

[Daytona R/T SE]

How would you compensate for restrictor plates which were used beginning in August 1970 at the Yankee 400 at MIS?     

The 71-72 Chargers always had them on every track. That's when Nascar was playing around with hole sizes, almost on a weekly basis!

No restrictor plates on the factory original cars we are discussing.

[Ghoste]

Except the question was to compare the speeds as known and without some documented 71-72 cars with non restricted Hemi's racing how can you do that?

[Daytona R/T SE]

Except the question was to compare the speeds as known and without some documented 71-72 cars with non restricted Hemi's racing how can you do that?

Time machine

[Ghoste]

And a rule change. 

[JB400]

Lets knock some rust off a few museum cars and find out.

[odcics2]

How would you compensate for restrictor plates which were used beginning in August 1970 at the Yankee 400 at MIS?     

The 71-72 Chargers always had them on every track. That's when Nascar was playing around with hole sizes, almost on a weekly basis!

No restrictor plates on the factory original cars we are discussing.

AHA!!    FACTORY cars - heads up!   Gotcha!   Was thinking race....

Hey -  Here is a candidate to test!       For a grin - compare this to the Petty raked car above. 
Stock, production car appears to have a little more air above the rear tires, yet similar rake!   

[1974dodgecharger]

How fast you plan on going? 

[Ghoste]

For some reason I had been thinking all along we were talking race prepped too.

[JB400]

I was under that impression as well.  Honestly, that's what I'd rather see.  It's pretty cool watching the old Trans Am series cars duking it out still.

[Daytona R/T SE]

The G-series wind tunnel report states that the standard 1971 Dodge set up for racing was not as good as the preceding E-series (Charger 500) race cars in terms of having greater axial force and significantly more rear lift. So there is the basic answer.

I'm going to call Doug's response the definitive answer that I was looking for.


Based on this, the '69 Charger 500 will have an aerodynamic advantage over the '71/'72 body style.

[Ghoste]

Seems like the fair answer to me.

[Daytona R/T SE]

Seems like the fair answer to me.

Yep,

And it comes from an excellent source.

[odcics2]

Seems like the fair answer to me.

Yep,

And it comes from an excellent source.

So, we're back to talking about massaged race cars??   
The "G" Series report applies to purpose built race cars.   

I think a street '69 500, with the T-bars cranked way down, would be better, IMO.   

[Ghoste]

If the report was for a race prepared car and the 500 still came in better than it would be fairly definitive no?