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As the title states. This is something ive always wondered. If you had two 300hp cars, one very aerodynamically efficient, and one not, would the more aerodynamic car always beat the other? Also can a lower powered car be faster than a higher powered car simply by its aerodynamic design? Looking at those wind tunnels in my front bumper has really gotten my mind wondering lol.
 

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As the title states. This is something I've always wondered. If you had two 300hp cars, one very aerodynamically efficient, and one not, would the more aerodynamic car always beat the other? Also can a lower powered car be faster than a higher powered car simply by its aerodynamic design? Looking at those wind tunnels in my front bumper has really gotten my mind wondering lol.
Wow, I hate hypothetical questions like this ...

Yes it would make a difference but not a noticeable difference. Car A might beat car B by .0000001 of a second over a given distance. The longer the distance the more likely the margin of victory to be greater.

On your car. No. Making any aerodynamic chances are not likely to yield substantial results. Plugging or otherwise covering those "wind tunnels" in your front bumper are likely to negatively effect engine cooling. Ford put them there for a reason.
 

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All other things like gearing and whatnot being equal, aerodynamics would certainly have an effect at higher speeds. It's negligible up to a certain point, but once you get going fast enough, pushing air becomes quite the task.
 

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Would it be faster? Yes
Would it be quicker? No
 

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The drag coefficient is just that, a drag term in the acceleration equation.

Ours is 0.31, according to the pdf, and we seem to have a frontal area of about 23 square feet, according to my math: 52.5" tall, with 5.7" ground clearance, and 71.8" wide.
(52.5-5.7)*71.8"/12^2=23.335 sq ft

It's proportional to velocity, and as long as you don't go supersonic, it's pretty straightforward. :grin2:

https://en.wikipedia.org/wiki/Drag_coefficient

In fluid dynamics, the drag equation is a formula used to calculate the force of drag experienced by an object due to movement through a fully enclosing fluid. The formula is accurate only under certain conditions: the objects must have a blunt form factor and the fluid must have a large enough Reynolds number to produce turbulence behind the object. The equation is

F_{D}\,=\,{\tfrac {1}{2}}\,\rho \,u^{2}\,C_{D}\,A
F_{D} is the drag force, which is by definition the force component in the direction of the flow velocity,[1]
\rho is the mass density of the fluid, [2]
u is the flow velocity relative to the object,
A is the reference area, and
C_{D} is the drag coefficient – a dimensionless coefficient related to the object's geometry and taking into account both skin friction and form drag.

The equation is attributed to Lord Rayleigh, who originally used L2 in place of A (with L being some linear dimension).[3]

The Fd term subtracts from the Force causing acceleration.

Acceleration is Force per mass, or A=F/m.

Ultimately, the rising curve that is the car's HP output will cross the drag force line, and that is the car's maximum speed.

I had an old subaru that the lines crossed about 80mph, downhill. :)
 

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Aerodynamics doesn't become a measurable consideration until you get up towards triple-digit speeds - and at those speeds, you'd be better off identifying your power curve and changing your gearing accordingly so your top speed is as close to your peak HP RPM as possible. And with an engine running hard enough to get you there, you want to be sure it's being cooled properly. There are a handful of calculators out there that will determine a car's theoretical top speed using CD, drag area and horsepower. I plugged in the numbers for a stock Mark VIII once and came up to a number close to 180 MPH, which is just about the same as that car's top speed (as determined by Ford at Bonneville in 1993) of 181 MPH - so it seems the calculator is accurate enough to bench race with. :)

http://www.markviii.org/LOD2/bonneville.htm
 

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Our cars are amazingly fuel efficient at freeway speeds; most cars peak about 60, my peak in the tbird is illegal. :)
 

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According to Automobile Catalog, MN12 Cougars have a drag coefficient of .36, while the Mark VIII slips by at .33. And Thunderbirds are even more slippery @ .31!
 

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I always heard .37 for MN12 Cougars supposedly the 87-88s are more slippery with .36.

IMO it makes very little difference in the real world. These cars have less drag than many supercars, in fact the Veyron has the same CD as a Cougar and tops out at, what, 254 mph? At real life road speeds you won't even notice, and there doesn't seem to be any discrepancy whatsoever between Tbirds and Cougars in terms of speed and highway fuel economy.
 

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According to Automobile Catalog, MN12 Cougars have a drag coefficient of .36, while the Mark VIII slips by at .33. And Thunderbirds are even more slippery @ .31!
I would have figured the Mark VIII would be slipperyer than the Tbird due to the "proud" front bumper giving it more a bullet-nose.

It's proportional to velocity-squared,
Fixed it for you. ;)
 
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