The AX Eco Project : 100 mpg target !

[HypermilerAX]

I already had wheel skirts, but they were quickly done and didn't look so good. A new version is in progress...
But it's winter and the cold temperatures don't make me want to work a lot on the car. That's why things don't progress fast.

The first fillup with the new tires is disappointing (3,09 l/100). It's exactly in the trend I had before. But I know there's been some wind and I'm trying to see a 0,2 l improvement so I'll have to accumulate some distance.

[renault_megane_dci]

Don't underestimate the impact of the very low temperatures we have had recently ...

[HypermilerAX]

Yes, indeed. Besides, the other thing that has changed is that now I'm doing fillups every time (800 km) as opposed to before where I did only partial fillups for up to 5000 km. So now, I'm seeing more the impact of daily weather and traffic conditions.
I had a terrible 3,3 l lately, I think I abused of the heating ventilation, 110W .
That is one of my worst FE except the one at constant 110 km/h (3,68 l).
I can already see that my current fillup looks good after 400 km (I know exactly how my tank gauge reacts).

[AndrzejM]

Originally Posted by HypermilerAX

I had a terrible 3,3 l lately

You're so spoiled! I wish I could see 3.3 in my fuel log

[renault_megane_dci]

You could but you would need to cruise around in a Citroen AX

[AndrzejM]

Just wait for my kill switch! I'm getting ~4l/100km without P&G so there's definitely an area to improve.

[HypermilerAX]

Some pics of my wheels. One has already a full cover for testing.

I have also mounted a device to measure accurately my fuel consumption. I have 2 flowmeters, one on the supply line, one on the return line and a unit subtracting the 2 values. It gives an incredible 0,1 mL resolution. That makes a 0,01 l/100 precision on a one-kilometer part and 0,001 l/100 on 10 km. Next step is to calibrate it : fillup, burn 40 L and refill. At first view, the flowmeters are 30% off (overestimating).
Then, the plan is to put the car in its original configuration and do FE tests at 90 km/h on a highway stretch and then to implement a new mod mod each time (the first one will be the changing the 5th gear ratio).

[AndrzejM]

Nice setup! And those Big Foot wheels I like it!

[Vekke]

Originally Posted by HypermilerAX

I have also mounted a device to measure accurately my fuel consumption. I have 2 flowmeters, one on the supply line, one on the return line and a unit subtracting the 2 values. It gives an incredible 0,1 mL resolution. That makes a 0,01 l/100 precision on a one-kilometer part and 0,001 l/100 on 10 km. Next step is to calibrate it : fillup, burn 40 L and refill. At first view, the flowmeters are 30% off (overestimating).
Then, the plan is to put the car in its original configuration and do FE tests at 90 km/h on a highway stretch and then to implement a new mod mod each time (the first one will be the changing the 5th gear ratio).

What was the price of your meters and do they have some flow restrictions? Are those meant for boat?

I tried to find cheap meter for my 6 liter turbo diesel scania, but what I found were over 1000€ per set.

[HypermilerAX]

The flowmeters are rather cheap (20€ each) but the unit was expensive : 150€. The gains (if any) won't pay off, it's more a "leisure expense" because I will play a lot with it. It will turn all my long commuting trips into tests.

The flow range goes from 0,03 to 3 l/min over 2 modes :
w/ nozzle : 0,03 to 1,8 l/min (high resolution)
w/o nozzle : 0,05 to 3,0 l/min (lower resolution)

They are not meant for boats, more for lab applications with low flows.

Products: B.I.O-TECH Flowmeter
You can browse their site, they have lots of choice.