Streamlined Citroen ZX

[CitroX]

The ZX upon a few other mods is getting a full slippery white vinyl wrap with some graphics. Will update with the final result.

[CitroX]

Best results so far! And finaly managed to perform my most accurate test yet. A-B 50.05 MPG (4.7l/100km), B-A 54.7 MPG 4.3l/100km. So the average consumption on a 247mile (400km) journey traveling at 59 mph (95km/h) was 52.27 MPG (4.5l/100km).

Modifications include front tire spats, full vinyl wrap with Grabmedia graphics, flush front fenders and increased tire pressure by 0.1 bar.

Profile pic:




At the factory:






Close up of the spats:


An interesting landmark in Lithuania - Hill of crosses

[elhigh]

The vinyl car wrap really cleaned up the appearance, covering seams and giving the whole car a consistent visual texture. Beautiful.

What are the crosses about? Here in the States a cross by itself is usually roadside, indicating someone died in a traffic accident at that location.

[CitroX]

Thanks. It really was a lot of work. Would have been impossible without some help and looks very neat now. I guess it even draws less attention now since it looks more like a normal car.

It's common to put crosses or candles at an accident site here too. But this is not the case. You can read about it here Hill of Crosses. It was brought down a few times as I remember.

[MetroMPG]

Car looks wonderful. Thanks for the update!

[JohnAh]

CitroX, your car looks really great! 4.5 L100 is definitely a nice figure! How is your driving style? Do you follow the traffic stream and speed? Do you plan your driving for DWB (driving without brakes)? What is your average cruising speed?

For a long time I was surprised by how much fuel could be saved by not using the brakes on my 40 year old Saab 96. I reduced fuel consumption from about 7 l/100km down to 6 L100 this way. My cruising speed at highway is about 80 km/h and the transmission is 4-speed. Many vintage Saab enthusiasts agree on a fuel consumption between 6 and 8 litres per 100 km on these cars.

When I started to practise PnG (pulse and glide) with engine shut down during the glide cycles and while standing still I have managed to reach down to only 4.5 l/100 km, and I have no aeromods at all! It would be verry interesting to see what could be done with Citroplanas if it is driven an a rather extreme way. I think it's mainly about hitting the sweetspot of the engine's BSFC-map, i.e. the area where the engine is running the most efficient, wich usualli is at about 70-90% of maximum throttle a little above maximum torque, any time the engine is running. If the engine can's be kept near the sweetspot, shut it down and coast until it's time for next "burn cycle".

[benphyr]

Driving Without Brakes

Originally Posted by JohnAh

...For a long time I was surprised by how much fuel could be saved by not using the brakes on my 40 year old Saab 96. I reduced fuel consumption from about 7 l/100km down to 6 L100 this way. My cruising speed at highway is about 80 km/h and the transmission is 4-speed. Many vintage Saab enthusiasts agree on a fuel consumption between 6 and 8 litres per 100 km on these cars.

Pulse and Glide

Originally Posted by JohnAh

When I started to practice PnG (pulse and glide) with engine shut down during the glide cycles and while standing still I have managed to reach down to only 4.5 l/100 km, and I have no aeromods at all! It would be very interesting to see what could be done with Citroplanas if it is driven an a rather extreme way. I think it's mainly about hitting the sweetspot of the engine's BSFC-map, i.e. the area where the engine is running the most efficient, which usually is at about 70-90% of maximum throttle a little above maximum torque, any time the engine is running. If the engine can's be kept near the sweetspot, shut it down and coast until it's time for next "burn cycle".

[JohnAh]

Thank's benphyr! It has taken some time for me to understand how this works, and that it really does. When I first read about PnG and that it can save up to 30% fuel I tried the wrong way and got quite disappointed. I later found out the importance of NOT giving full throttle, because of the carburettor's (or fuel injection's) full throttle enrichment.

To save 30% it is also of great importance to stop the engine when acceleration is not needed. "Digital driving" may be another way to put it. I often think about where you find the world's most skilled eco-drivers - At NASA and others in aerospace industry!
Rocket engines usually work quite digital in on/off cycles, or burn cycles. All excess speed from a too long burn cycle will sooner or later have to be counter-acted and the only way to reduce excess speed in space is a reverse burn cycle, wasting precious fuel. The only way to save maximum fuel is to never burn more than just needed to reach the goal. If you must use the brakes, you have failed!

[NothingFace]

Great looking boat tail, the one on the aerocivic looked kinda funky, your's looks preety professional.

[CitroX]

Originally Posted by JohnAh

CitroX, your car looks really great! 4.5 L100 is definitely a nice figure! How is your driving style? Do you follow the traffic stream and speed? Do you plan your driving for DWB (driving without brakes)? What is your average cruising speed?

Thanks, impressed by your driving style results. When I began this project it was mostly about the gains of the aeromods. And I kind of stuck to that for now. So I'm driving with a distance from other vehicles and doing everything I can to keep the speed as consistent as possible. The previous and most accurate test I've done was at 95km/h (59mph), which is 5km/h (3mph) more than usual.
The mileage could definitely be improved quite easily:
Slimmer summer tires, using your mentioned driving methods, mirror delete, lower suspension, giving the engine a simple spark plug, filter, oil change etc.,
and I always drive with a passenger and full tank of fuel.