Why Cd vary so much within same models of car?

[freebeard]

Message is apparently browser dependent. Chromium:

"This site can’t be reached
Check if there is a typo in https.
DNS_PROBE_FINISHED_NXDOMAIN"

[Piotrsko]

Kill the first htp:// and the second / on https, add a : after the htps

https:/www.car-engineer.com/mercedes-cla-is-the-most-aerodynamic-production-car-of-the-world/

Works in opera with security on. OR you can go to www.car-engineer.com and just do a search

The htp:// is an undefined web node caused by quoting something on this site? I believe it is part of the underline and change color or font process so it is clickable because you will notice my corrected string does not direct you to the site.

[freebeard]

It's easier than that.

The URL entry field comes prepopulated with 'http' preselected. Press right arrow or click in the field to deselect and paste and you get doubled up tags. One less action to make it work.

[aerohead]

Originally Posted by AEOLUS

I dont know in which wind tunnel is meassurments done..
CLA has 1480kg, Merc. claim 180 blue efficiency has Cd=0.22 and 250CDI in test has shown Cd=0.30.
This two cars are 99.9% identical, to me is strange so big difference in Cd.
What do you think?

Did you look at the nineteen detail optimizations specific only to the CLA 180 Blue Efficiency?
If each modification produced a drag reduction of only 4.2-counts, together, we'd have the delta- 0.08.

[AEOLUS]

Originally Posted by aerohead

Did you look at the nineteen detail optimizations specific only to the CLA 180 Blue Efficiency?
If each modification produced a drag reduction of only 4.2-counts, together, we'd have the delta- 0.08.

Yes but 180 model(without BE) has 0.23, so it seems all this features reduce just for 0.01...

[aerohead]

Researchgate had some info:
CLA 250 Euro-spec, Cd 0.28
CLA 250 USA=spec, Cd 0.30 @ A2 Wind Tunnel ( Don Sherman, CAR and DRIVER )
M-B B180 Blue Efficiency with eco package, Cd 0.24
CLA 180 Euro-spec, Cd 0.23
CLA 180 Euro-spec Blue Efficiency, Cd 0.22
--------------------------------------------------------------------------------------
The A2 Wind Tunnel measurement would not compare to any M-B measurement.
--------------------------------------------------------------------------------------
baaf_ks.com reports that 230,000-hours of wind tunnel time was spent on the Cd 0.22 variant.
--------------------------------------------------------------------------------------
Some of the reporting is so non-specific, I'm no longer sure what the journalists are actually reporting.
Ideas?

[AEOLUS]

Originally Posted by aerohead

Researchgate had some info:
CLA 250 Euro-spec, Cd 0.28
CLA 250 USA=spec, Cd 0.30 @ A2 Wind Tunnel ( Don Sherman, CAR and DRIVER )
M-B B180 Blue Efficiency with eco package, Cd 0.24
CLA 180 Euro-spec, Cd 0.23
CLA 180 Euro-spec Blue Efficiency, Cd 0.22
--------------------------------------------------------------------------------------
The A2 Wind Tunnel measurement would not compare to any M-B measurement.
--------------------------------------------------------------------------------------
baaf_ks.com reports that 230,000-hours of wind tunnel time was spent on the Cd 0.22 variant.
--------------------------------------------------------------------------------------
Some of the reporting is so non-specific, I'm no longer sure what the journalists are actually reporting.
Ideas?

Where can I find drag coeficient of CLA C117 180CDI?
(where did you find this numbers)
It is very hard to find this numbers, they only report 0.22 for BE and 0.23 for "others models "in CLA class..

I still cant post links...

[aerohead]

WIKIPEDIA credits the CLA Coupe (C117) CLA 180 CDI ( 107-hp ) Euro-spec Blue Efficiency with Cd 0.22:
* A-pillars
* Exterior mirror housings and rear shape
* Diffuser
* Underbody
* Radiator shutters
* Wheel trim
* Serrated wheel deflectors ( all for wheels )
* 205mm section tires
--------------------------------------------------------------------------------------
The Cd 0.30 is from Don Sherman @ A2 Wind Tunnel, and has been called into question by some ( the Toyota Prius also tested, recorded a higher Cd than what Toyota measured, same for the Honda Insight and Nissan LEAF ) Only the Tesla S registered a Cd equal to it's published value [ then some report that Tesla's value was actually Cd 0.26! ].
The CLA 180 Euro-spec BE car isn't available in the USA. They must have tested something other than the Cd 0.22 variant.
A real can of worms!

[AEOLUS]

Originally Posted by aerohead

WIKIPEDIA credits the CLA Coupe (C117) CLA 180 CDI ( 107-hp ) Euro-spec Blue Efficiency with Cd 0.22:
* A-pillars
* Exterior mirror housings and rear shape
* Diffuser
* Underbody
* Radiator shutters
* Wheel trim
* Serrated wheel deflectors ( all for wheels )
* 205mm section tires
!

CLA C117 180 Blue Efficiency with diesel engine? (I thought only comes with petrol engine.)

Why I cant find any 180 cdi or d Blue Efficiency on internet to sale??

[aerohead]

Originally Posted by AEOLUS

CLA C117 180 Blue Efficiency with diesel engine? (I thought only comes with petrol engine.)

Why I cant find any 180 cdi or d Blue Efficiency on internet to sale??

Does 'CDI' stand for 'Compression Direct Injection' ? I'm not familiar with Daimler's nomenclature.
Whatever engine produces 107-horsepower is supposed to be the Cd 0.22 car's engine.
Seven (7) engines and two (2) transmissions are available for the CLA, however, only the 107-hp engine is in the Cd 0.22 version.