Bluemotion Benefits: Maximize Your Savings

Hi.

The "older" Bluemotion, specifically the 1.9 PD Trendline with its features, has undergone some modifications that make it more fuel-efficient.
There are already threads that list the differences.

Here, I would like to try to explain the retrofit options.

Let's start with an overview:

Not easily retrofittable.
- other engine software.
- related to: gear indicator
- different gearbox
-15/-8 mm wedge-shaped suspension.
- BLUEMOTION lettering on the grille.

It's not always a good idea to upgrade (especially with the 125 kW engine).
- Partially closed radiator grille.
- No ducting to the front brakes.
- Tire (?)

Simple and interesting.
- Cover for the left fog light closed (3C0 853 665 C - already done).
- Longer air vent trims in the area under the rear seat bench (in planning).
- BLUEMOTION lettering on the rear (6Q0 853 675 R - funny on a blue car ).

After browsing an aerodynamics book, it seems that the underbody panel is the cheapest and most quickly implemented modification one can make.

Is anyone interested in joining? Can I contribute anything?
Greetings.
m;

Quote:

After browsing an aerodynamics book, it seems that the underbody panel is the cheapest and most quickly effective modification one can make.

Measure the rolling resistance on the road (e.g., by rolling the car at 100 km/h) with and without the underbody panel? Is it possible to obtain reproducible and measurable results?

Best regards, Rainer.

Certainly, the easiest thing to add is the lettering on the rear. Unfortunately, I couldn't find any information about its effectiveness in the literature. Audi specifies the complete underbody paneling for the A4 8E with a cw value of -0.019 and for the 8k with -0.029. However, it doesn't state how optimized the underbody was before.

The underbody paneling is likely the most effective modification you can add. Following that is lowering the vehicle. Rolling resistance tires also make a significant difference. The potential savings in rolling resistance, achieved through careful selection and reducing tire width, are said to be in the lower double-digit percentage range.

The numerous Econetic models from Ford also operate on this principle: narrower tires, lowered suspension within a practical range, and aerodynamic modifications. To my knowledge, Ford makes no changes to the engines, and I don't believe that modified transmissions are used, given the relatively small price difference for an Econetic model.


I've written about this somewhere before in this context: My Peugeot 206 eco also works on this principle. It has a slightly longer gear ratio, is lowered by 30 mm, has an underbody panel, bumpers from the CC convertible, smaller exterior mirrors, and (theoretically) low rolling resistance tires. In addition, Peugeot tried to make the eco model lighter. How much difference that makes remains a secret, because the eco model has the same manufacturer's approval (ABE) as the standard models, and minor things like the lowering can simply be approved and registered individually during the initial registration.

In the end, I can achieve a fuel consumption figure just below the manufacturer's specifications with the 206 Eco. With the standard models, this is usually practically impossible.

delta cw -0.03 can already increase the maximum speed by 9 km/h .

The underbody components of the A6 (2004) result in a delta cw value of -0.031.
(apparently compared to the bare underbody).

Both comparisons are described in the Hucho document.

Okay, the "rear diffuser" that I want to take from the Bluemotion model only provides a reduction of 0.005.
But it's also a little bit about "just because I can" .

m;

The exposed underbody can vary in its finish. If the Passat doesn't have any other cladding, the metal could have been made smoother and less prone to imperfections than if it was known that a panel would eventually be placed underneath it.

A side effect is a reduction in noise.

I'm sorry, I don't quite understand what you're trying to say.

Every Passat has a lower panel. The BM models have a slightly larger one. They have panels that extend all the way around the rear wheel suspension (longitudinal links).

m;

If he's already disguised, and my documents don't indicate otherwise, then the effect will be correspondingly small.

As I mentioned, the rear fairing on the A6 has a drag coefficient (cw) of -0.005 according to Hucho.
The size of this is roughly equivalent to the difference between what BM has and what I have.

Since I happen to have an A6 and a BMW "within my family/circle," I can also take a look.

Maybe this -0.005 will help and I can be happy about it, so that it can compensate for the coked PPDEs }.

m;

Okay,
I think I got it pretty well.
Blue is my Sportline - so, it's the standard paint job.
Silver (in the Autostadt) offers the Bluemotion model, where the additional cladding simply attaches to the standard cladding.

So, you need to get parts 3C0 825 101 and 3C0 825 102, plus the screws, which will cost around 81 EUR... oops, actually it's more than that.

m;

"Do these 81€ really make sense? I don't think you'll really notice the savings because of just one small cover."

They are not that small.

The left one is about 50 units long, and the right one might be even longer.

Let me do some calculations.
Costs 80 EUR.
Let's say diesel costs 1.10 EUR per liter.
Are we talking about 72 liters?
If I want to have those 72 liters of fuel last for 100,000 km, it needs to achieve a fuel consumption of 0.072 liters per 100 km.

Hucho states that a delta-cw value of -0.030 results in a fuel consumption reduction of 0.1 to 0.2 liters per 100 kilometers.
The rear underbody panels on the A6 provide a delta-cw value of -0.005.

OK, it might be tight .
Then I just need to negotiate a bigger discount.

Okay, then it's several parts! You might get lucky and find a cheaper one at a car wrecking yard, one that has been cold-formed . Otherwise, it's faster . Or, you could cut plastic sheets from the hardware store, but it wouldn't be professional and it would be time-consuming to assemble .

I'm very curious to see if anyone actually notices a difference in fuel consumption! It would be great if you could report the fuel savings after driving 5000 km with this fairing. The person behind the wheel also has the greatest potential for savings if they drive with awareness and foresight }, compared to a new driver who just accelerates, brakes, and drives erratically.

I believe that...
I will never be able to definitively prove an effect.

My driving needs fluctuate quite a bit. Sometimes I'm driving around the city for days, then other times I'm taking family trips across the countryside, and occasionally I like to push the car to its maximum speed.

Since I purchased it, the price has been fluctuating wildly.

Maybe I'll order one sometime and see if it fits...

m;

It's the same for me! Sometimes I drive to Austria on the weekend for snowboarding, to visit friends, and even for skydiving. Other times, I go to Tuscany to see my relatives (I prefer to fly there, it's much cheaper, and for that 1.2-hour flight, I can use my cousin's old car, because she's always happy when I get it running again ). This results in an average fuel consumption of 5.8 liters. In my opinion, that's a good value for an ARL (Audi rally legacy). I don't drive like an old man; what's the point of having an ARL if I do?

Another crazy idea:

Retrofitting Attica

The Insignia and Scirocco have that feature.
http://tequila.homeip.net/Passat/Scirocco_Attika.jpg
http://tequila.homeip.net/Passat/Insignia_Attika.jpg

m;