Aerodynamics of electric vehicles ...

[930.engineering]

Had to look at Golf vs E-Golf specs as the E-Golf wasn't in the above test.
E-Golf is .28 so about mid-pack and VW literature shows it is 10% better than
ICE Golf so that is about .31. Seems VW left quite a bit on the table for aero
on the ICE Golf as most of the mods for the 10% improvement would be ok
on the ICE, yeah maybe the underbody cladding would not be 100% due to
accommodating a hot exhaust and the grill shutters might not be able to stay
closed as long/often but the rest is really just aero treatment.

Very true, VW designed the Mk7 to be powered electrically in mind.
Yes, it's mainly grill (closed) and underbody panels what makes the difference.
There are also some visible details like the roof spoiler (same as GTI, GTE, GTD,
R, and R-line equipped Golfs) including the side fins next to the rear window.
Remember VW also sold dedicated BlueMotion models in Europe (1.6 TDI first,
1.0 TSI later) which both came with extended use of underbody panels for a cd
of 0.29 as far as I remember.
That said, I added 'belly pan', a tunnel cover (from GTD) and a rear axle cover to
my GTI, all OE parts for comperatively little money. My intention wasn't drag only.
A smoother underside also decreases lift and improves stability, and it also helps
to reduce noise.

One thing I have noticed and wondered about my E-Golf is it has the vents for the
front wheel air curtains but I cannot for the life of me figure out where it gathers the
air as the LED bumper running lights are pretty much flush mount with no air openings.

My GTI (no fog lights) has fully functional air curtains just like several BMWs have.
I can see through them (from front to vertical slots in the wheel well and vice versa).

1986 Merkur, Drag coefficient 0.26.

The Ford Sierra (as it was sold in Europe) was reported to have a cd of 0.34, the XR4i
with 0.32. Where you you have your number from? A cd of 0.26 is just unrealistic for
a passenger car that started production in 1982 and entirely lacks underbody panels.
Sadly a vast number of reported cd numbers is actually true, that's no news.
.

 

[JohnnyG]

Very true, VW designed the Mk7 to be powered electrically in mind.
Yes, it's mainly grill (closed) and underbody panels what makes the difference.
There are also some visible details like the roof spoiler (same as GTI, GTE, GTD,
R, and R-line equipped Golfs) including the side fins next to the rear window.
Remember VW also sold dedicated BlueMotion models in Europe (1.6 TDI first,
1.0 TSI later) which both came with extended use of underbody panels for a cd
of 0.29 as far as I remember.
That said, I added 'belly pan', a tunnel cover (from GTD) and a rear axle cover to
my GTI, all OE parts for comperatively little money. My intention wasn't drag only.
A smoother underside also decreases lift and improves stability, and it also helps
to reduce noise.




My GTI (no fog lights) has fully functional air curtains just like several BMWs have.
I can see through them (from front to vertical slots in the wheel well and vice versa).




The Ford Sierra (as it was sold in Europe) was reported to have a cd of 0.34, the XR4i
with 0.32. Where you you have your number from? A cd of 0.26 is just unrealistic for
a passenger car that started production in 1982 and entirely lacks underbody panels.
Sadly a vast number of reported cd numbers is actually true, that's no news.
.

Read it somewhere. It was long ago.

 

[Rmay635703]

Aerodynamics are the most important aspect of EV design this 1000 mile EV, uses a smaller battery than Tesla offerings (as an example)

https://www.theverge.com/2020/12/6/22157109/aptera-ev-solar-charging-vehicle

 

[930.engineering]

Sadly a vast number of reported cd numbers is actually true, that's no news.

Should read 'a vast number of reported cd numbers is actually untrue'.
.

 

[JohnnyG]

Very true, VW designed the Mk7 to be powered electrically in mind.
Yes, it's mainly grill (closed) and underbody panels what makes the difference.
There are also some visible details like the roof spoiler (same as GTI, GTE, GTD,
R, and R-line equipped Golfs) including the side fins next to the rear window.
Remember VW also sold dedicated BlueMotion models in Europe (1.6 TDI first,
1.0 TSI later) which both came with extended use of underbody panels for a cd
of 0.29 as far as I remember.
That said, I added 'belly pan', a tunnel cover (from GTD) and a rear axle cover to
my GTI, all OE parts for comperatively little money. My intention wasn't drag only.
A smoother underside also decreases lift and improves stability, and it also helps
to reduce noise.




My GTI (no fog lights) has fully functional air curtains just like several BMWs have.
I can see through them (from front to vertical slots in the wheel well and vice versa).




The Ford Sierra (as it was sold in Europe) was reported to have a cd of 0.34, the XR4i
with 0.32. Where you you have your number from? A cd of 0.26 is just unrealistic for
a passenger car that started production in 1982 and entirely lacks underbody panels.
Sadly a vast number of reported cd numbers is actually true, that's no news.
.

Should read 'a vast number of reported cd numbers is actually untrue'.
.

Untrue, and ever changing. A 30 second google search shows the Xr4Ti with a coefficient of .33. And as you point out, pretty respectable for a car from 1986/7 without underbody panels of any kind. I imagine it would have exceeded that .26 numbers if plastic panels would have been installed.

https://newoldcars.com/1987-merkur-xr4ti/