Aerodynamics should benefit BOTH Top Speed and MPG, right?
 

Hey guys, just wanted to make sure my line of thinking was correct. By improving the aerodynamics of the vehicle to get better MPG, we should in theory be able to have a higher top speed as well, right?

Are there other variables that I'm not considering?

Not necessarily. If you have a really overpowered vehicle, the top speed is limited by the engine redline and gearing.

But even in that case it will improve the time to reach top speed.

Reducing the aero drag will increase top speed and mpg, all other factors being equal.

regards
mech

Lift

F1 cars intentionally use additional aerodynamic drag in order to produce negative lift .. ie keep the car pressed firmly down against the road .. In that case reduced aerodynamic drag would reduce the aerodynamic down force they normally design into the the vehicle .. soo they have to compromise between desire for less wind resistance to move forward against ... vs .. also the desire for more down force pressing the car against the road.

(plus everything everyone else already said as well)

As they say ... use the right tool for the job .. sometimes .. in some contexts .. intentionally designed increased aerodynamic drag can be a net performance benefit .. but it isn't always so in all contexts.

- - - - -

Also for 'other variables' ... is there any 'cost' to reducing the aerodynamic drag ?... like increasing the weight , etc .. That will depend on the method used to reduce the aerodynamic drag .. A boat tail will add weight for example ... + & - ... if more + it's a net benefit.

right. gotta keep it stable at speed or you crash like this land speed record Insight
http://ecomodder.com/forum/showthrea...mph-27588.html

I seriously doubt he will be trading his car for an F1. speeds above a certain part play into "lift" but normal cars needn't worry.

again, highly doubtful speeds will reach 190.
I am pretty sure he is asking about a passenger car at highway speeds.

No, the OP specifically asked about TOP speed. I don't think there are many modern (say the last 40-50 years) that don't have top speeds well in excess of highway speeds - German autobahns excluded, of course :-)

top speed / mpg
 

If you have an actual drag-limited top speed,where the engine is actually at redline,then,with proper gearing,according to Hucho,a 30% drag reduction will equate to about a 10% increase in top speed at redline.
If re-geared,my T-100 would have done 111-mph.
Now,with the streamlining package she's good for 125-mph.
And + 9-mpg on the highway.
http://i1271.photobucket.com/albums/...ntitled1-4.jpg
http://i1271.photobucket.com/albums/...ohead2/100.jpg
http://i1271.photobucket.com/albums/...ntitled2-4.jpg
http://i1271.photobucket.com/albums/...ad2/12-066.jpg
http://i1271.photobucket.com/albums/...ad2/12-064.jpg
http://i1271.photobucket.com/albums/...ad2/12-065.jpg

Short answer: yes.
AND you improve acceleration at higher speeds.
AND you improve speed and acceleration when driving into a strong headwind.