Citroen AX Diesel from Portugal

[NothingFace]

2/3 of my daily commute is highway, it's just in 1 or 2 miles of stop and go traffic since I don't really go into Lisbon(I get out on the last exit before).

I can make my schedule at school (within what is avaiable) so I'll try to get the classes starting at 8AM and that way I'll avoid the stop and go bit because traffic is only an issue after 8.

I'm still tryning to figure out if it is better to coast in gear or in neutral with the engine on .

[cRiPpLe_rOoStEr]

Neutral-coasting may be a little more efficient, but I'd still rather coast in gear (can still disengage it thru the clutch) for safety reasons. Anyway, since you're considering to do some aero mods, maybe you'd be better off if you could still manage to counterbalance the weight add-ons with some weight reduction at other random spots. OK, I know it may sound kinda hard to do so because the AX is already lightweight...

Anyway, have you never considered to turbocharge it?

[euromodder]

Originally Posted by NothingFace

2/3 of my daily commute is highway

Aeromods should give you a benefit then.

I'm still tryning to figure out if it is better to coast in gear or in neutral with the engine on .

With a 1500 diesel, I'd expect you get a fair bit of engine brake when you release the throttle ?

Coasting in neutral will make you roll a lot further than in gear.
But that means you have to remember to shift in neutral a lot earlier as well
Or only accelerate to a slower speed - just enough to get to the next turn, bend in the road, traffic lights , ...with an appropriate speed.

Of course, if you have to control your speed when going downhill, or when you need to slow down anyway, you coast in gear - and use no fuel at all.


Coasting in neutral becomes inefficient around 20 to 15 km/h or so :
you burn too much fuel/h and would need too many hours to make the theoretical 100km.
@ 0,5 L/h and 20 km/h, you're still using 2,5 l/100km
@ 0,5 L/h and 12.5 km/h , you'd be using 4L/100km - which is higher than what you could get out of the AX.

[NothingFace]

I will try to coast with with the clutch disengaged then.

The highway in my comute has a fair bit of ups and downs so I'll probably get a fair bit of coasting.

Yes engine braking is preety severe since the compression ratio is a staggering 22:1.

Turbos do help make diesels be more eficient but it would be expensive and ilegal.
Taking the back seats out would also be illegal since I have a five seater. Its about 250€ fine + inspection.

[cRiPpLe_rOoStEr]

Originally Posted by NothingFace

Turbos do help make diesels be more eficient but it would be expensive and ilegal.
Taking the back seats out would also be illegal since I have a five seater. Its about 250€ fine + inspection.

That sucks. BTW why turbocharging your current engine would be illegal?

[NothingFace]

Because any change to original spec is technically ilegal.

This means any change to suspension or engine if the police sees it they give you a fine and apprehend your cars documents, to get them back you need to go through a very strict inspection. And I aready have a different engine than original so It's better to keep a low profile since the engines are preety similar appearance wise.

If you want to have changes legal you need an engeneer to make a project and put all the changes in the cars documents.

Hopefully I can do this when I get my Masters Degree. but until then its not worth it since the fine is half of what I paid for the car in the first place, and I wouldn't whant to buy another one.

[cRiPpLe_rOoStEr]

Gotta hate all that bureaucracy.