Rear end aerodynamics
12-25-2007, 04:54 AM
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Originally Posted by titanium' post='508232' date='Dec 18 2007, 04:31 PM
After driving a couple of days on our salty roads the car looks like this on the rear end. Not a pretty sight 
Attachment 42021
The rest of the car looks really fine. Nothing to be ashamed about.
The thing is, I really hate a dirty car so much time is spent washing, washing and again washing . . .
If you look at the picture below you can see that there is a sharp border between the rear end and
the side of the car. The airflow seems to produce a whirl over the rear end and that sucks up all
the dirt from underneath the car. Not so good !
I?ve had several estates and none of them have had theese severe problems with "blackened out" rear end
Attachment 42022
So what can be done ?
Do I have to drive like this ? Disguised
Attachment 42023
Any thoughts ?
Attachment 42021
The rest of the car looks really fine. Nothing to be ashamed about.
The thing is, I really hate a dirty car so much time is spent washing, washing and again washing . . .
If you look at the picture below you can see that there is a sharp border between the rear end and
the side of the car. The airflow seems to produce a whirl over the rear end and that sucks up all
the dirt from underneath the car. Not so good !
I?ve had several estates and none of them have had theese severe problems with "blackened out" rear end
Attachment 42022
So what can be done ?
Do I have to drive like this ? Disguised
Attachment 42023
Any thoughts ?
...but considering the conditions you're driving in, its gonna happen regardless.
12-26-2007, 12:32 AM
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Originally Posted by Heelsonwheels' post='510436' date='Dec 25 2007, 02:54 PM
One of previous SUV's had a roof spoiler which worked fairly well to direct the air down against the rear end and window...but it still got dirtier than the rest of the truck....maybe invest in a pair of long rubber gloves... ...but considering the conditions you're driving in, its gonna happen regardless.
...but considering the conditions you're driving in, its gonna happen regardless.I?ve been an a 1000 km trip just before Christmas, all on salted wet roads. And the rear is FILLED with black dirt. The rear plate isn?t visible at all. 2 hours and 2 liters of degreasing later the car is respectable again. (deep sigh)
Rubber gloves was needed
And Yes I think you are right about the spoiler. I once had a Volvo XC with a roof spoiler, which made quite a differrence in ceeping the rear end cleen. The "spoiler" on the E61 isn?t that functional I think as it?s rather small.
Ha anyone seen a bigger spoiler for the E61 ? ?
12-26-2007, 06:19 AM
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My Ride: 530D touring MY 07 facelift
M-sport, automatic, Xenon, logic 7, Spacegrey , Cream Dakota, PDC, Comfortseat
Delivery in april -07
You will have this problem if you drive Estate/Touring cars when the roads are dirty.
I have had several Volvo V70 Estate before my E61, it took only 3-4 km before the Volvo Estate looks like your E61 after 1000 km.
So be happy that you don?t drive a Volvo V70
I have had several Volvo V70 Estate before my E61, it took only 3-4 km before the Volvo Estate looks like your E61 after 1000 km.
So be happy that you don?t drive a Volvo V70
12-26-2007, 09:00 AM
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Originally Posted by titanium' post='510634' date='Dec 26 2007, 10:32 AM
Ha anyone seen a bigger spoiler for the E61 ? ?
AC Schnitzer E61
12-27-2007, 12:41 PM
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Originally Posted by PSB' post='508240' date='Dec 18 2007, 11:45 PM
i dont think there is much you can do about this .. its the physics of the car .. when u drive a low pressure area is built behind the car eddie circles are formed in the air .. this will pick up any dirt behind and since there is snow there are more things in the air to pick up .. i guess a hatchback will go thru this problem more than a salon because its less airo-dynamic
All right, I don't wash my car too often..
12-29-2007, 03:41 AM
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Thoughts about aerodynamics continues:
The strangest thing happened this week.
There was some heavy rain on christmas day. The next day when the streets were still a little wet I took a ride with my (as always) newwashed car.
But . . . it didn?t get any dirt at the rear window at all after driving a couple of km. Strange
Have thought much of this and my conclusion is that it?s the salt on the road that is the problem. The salt+dirt must stick to the tires in quite a different way than what the water+dirt does.
With salted roads I could drive from the carwash just 1 km and the rear end is full of dirt.
Now I?ve driven 20 km and the rear is still acceptably clean.
Perhaps we could have a competition: dirtiest car wins ! Post your pics here of your dirty car
To Narvselius: The Schnitzer spoiler doesn?t look that much bigger than the original.
But I?ve found one that does: Mathes
But they probably don?t sell just the spoiler. They want to redo the whole car.
The strangest thing happened this week.
There was some heavy rain on christmas day. The next day when the streets were still a little wet I took a ride with my (as always) newwashed car.
But . . . it didn?t get any dirt at the rear window at all after driving a couple of km. Strange
Have thought much of this and my conclusion is that it?s the salt on the road that is the problem. The salt+dirt must stick to the tires in quite a different way than what the water+dirt does.
With salted roads I could drive from the carwash just 1 km and the rear end is full of dirt.
Now I?ve driven 20 km and the rear is still acceptably clean.
Perhaps we could have a competition: dirtiest car wins ! Post your pics here of your dirty car
To Narvselius: The Schnitzer spoiler doesn?t look that much bigger than the original.
But I?ve found one that does: Mathes
But they probably don?t sell just the spoiler. They want to redo the whole car.
12-31-2007, 01:48 AM
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e60-61 has very smooth underbody with very sofisticated details... take a look at other cars... no idea about something like rear completly covered etc... I have a pic of Ford Focus Turnier underbody :-))) it is more like a huge airdam acting like a parachute .-)
12-31-2007, 05:50 AM
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Originally Posted by titanium' post='511598' date='Dec 29 2007, 07:41 AM
With salted roads I could drive from the carwash just 1 km and the rear end is full of dirt.
Now I?ve driven 20 km and the rear is still acceptably clean.
Now I?ve driven 20 km and the rear is still acceptably clean.
12-31-2007, 06:07 AM
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Originally Posted by phelix' post='512200' date='Dec 31 2007, 03:50 PM
Road speed must factor into it; below perhaps 70-80 kph there isn't enough spray thrown up to get sucked back onto the window?
If the roads are plain wet, without the salt/sand mixture, your speed-conclusion is correct I think.
And Streetpro?s idea about the smooth underbody is a nice thought. I have never seen a car with a smoother underbody
Wishing you a Happy New Year
05-21-2008, 05:16 AM
#20
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Originally Posted by titanium' post='508232' date='Dec 18 2007, 11:31 PM
Any thoughts ?
