Thinking about an econo-box commuter

[Billzilla]

Constant RPM diesels like generators are much more efficient then the ones they need to use in cars.

Yep - You can make them just big enough to run at full throttle (to reduce parasitic losses at part throttle) so that they make enough power to drive the generator to drive the electric motor, etc.
But for sure it's intorducing extra losses in the stages that go from the generator to the electric motor. But I'm not sure if those processes would be hugely less efficient than an otherwise conventional diesel-gearbox setup.

[Jim]

AND you can run them on chip oil, or wog grade olive oil ($1.20/L)

[Roadsailing]

deisels don't have throttles, AFAIK thats part of the reason they are more efficient than their petroleum bretheren.

Audi (i think) made a 3L diesel car, it ran at full "noise" periodically, kinda like PWM.

suppose you may have a point on the losses, after all we know a car will lose at least 20% of its engine power on the dyno

aerodynamics will be worth looking at before anything else i reckon, especially at freeway speeds.

[Jim]

deisels don't have throttles, AFAIK thats part of the reason they are more efficient than their petroleum bretheren.

:rotflol:

[Billzilla]

deisels don't have throttles, AFAIK thats part of the reason they are more efficient than their petroleum bretheren.

Dang, yes of course ....

I bow to Jimbo, our diesel expert.

[Gus The Snail]

Diesel Gemini , make your own bio fuel , profit!

The isuzu diesel donks were ahead of their time , i think its about 750km from a 52 litre tank , 5 speed , you can even get a/c in a gem , and because of the 4x100 stud pattern , wheel choice is huge , so you could throw on some 175/70/14 tyres , lower it , front spoiler , and have a pretty good handling car with economy ( and the bonus of torquey line lockers )

[Mr Purple]

Do you care about legality?
If you do, it'll definitely be cheaper to stick with a stock car.


I believe that, unless someone's on a fuel-economy mission (which isn't going to happen all the time), the car actually needs to be limited in order to get the best economy out of it; otherwise you have a tendency to push it, and there goes your fuel economy.
The 3cyl Swifts used to use less fuel than the GTi's ... I reckon that if the GTi's could have their power limited to what the 3cyl cars put out, the more efficient GTi engine would probably make the GTi more fuel efficient.
Dunno how you'd tune this in though ... electronic throttle body?

Well, you'd also save $50 per year on rego for a three cylinder. Working on say 10,000km/yr that would possibly work out to up to a 3.2% saving on your 'economy' in general...

Unfortunately the frequent rebuilds you'd need and the fact you don't actually have one sitting around would negate that. I vote series 1 base model swift, GTI engine, and everything thrown out but the 'go ' and 'stop' bits.

And get a jockey to drive it.

[biscan]

Would an extremely heavy flywheel assist with fuel ecconomy on the freeway ?

[Motorsportlady]

Smart Car might be a good alternative?

[Mr Purple]

I have a solution:

http://cars2.ebay.com.au/Suzuki-Van-...mZ120303129514

[rj_astra]

series hybrids are terrible for fuel economy on the highway, or the city for that matter, how the fuck is diesel - generator - wires - electric motor - wheels going to be more efficient than diesel - gearbox - wheels?.

Go tell GM that about the Chevy Volt

Pity you can't afford an old Honda Insight. They are still one of the most economical cars in the world... even on the highway.

How much are VW Golf Mk 1 GTDs worth on the market nowadays?

[Masier]

3 cylinder turbo diesel charade if you can find one. You will be hard pressed to beat it.

[tremolo]

What's the objective of the exercise? Is it to build a fuel-efficient car or to save money?

[Turbo 351]

Another vote for LPG Bill, I have a tank here you can have for free, $200 worth of impco parts from e-bay, a few hundred more for install and plate, will cost you sub $1000, and you get $2000 back from the government (It does work, i did it on the cressida). Filling up at 67c is nice!!
So you get money back for doing it, cheap per Ltr to fill, even though it will use a little more per 100km, get to use your motec on something else, or sell it. I cannot see any negitives.
My cressida on LPG runs like a champ, no bad side effects at all, and it is a cheap arse old Impco carby set up.

[Fatboy]

Well this thread is almost a waste of time ....
I would try for up around 70mpg, or about 4l/100km.
That's better than the CBR250 gets, and I wouldn't get wet when travelling in the rain.
The train and bus are useless to me, as I'd still have to either walk kilometres at either end or catch a taxi. Having a pretty average-looking car is also a far better thing than leaving the WRX out at the airport in the open for days at a time.

Bill, i think point most of us are trying to make is the money you spend modifying would run it for ages if you're only saving say 1 litre per 100kms...

Buy a cheapish reliable shitter and just drive the bloody thing. Or have i missed the point yet again ?