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Wondering if anybody has come across info on successful diesel conversions into Sube's ? I came across a reference for a 1.9 TDi VW engine, but have not been able to find any real info as yet.

Not something I am planning on doing in a hurry, but I am kinda considering it as the next project once the EJ to Brumby is done.

I've heard of EA81 Diesel engines (from FHI forklifts apparently) but never seen any. I've been told they're gutless wonders, however who knows what you could achieve with a turbo and a correctly ground cam.

Check out this page (sorry, it ISN'T a diesel vortex but it sets the scene):
http://utterpower.com/10hp_chevy.htm

I've recently been looking at diesel motorbike conversions in an ongoing effort to prepare for peak oil.

What I've discovered is that when cruising, fuel consumption of a vehicle is (approximately) directly proportional to the following properties:
air density
coefficient of drag
frontal area
specific fuel consumption of engine (mass of fuel burnt per unit energy released)

... and vehicle fuel consumption is approximately proportional to the SQUARE of velocity.

Motorbikes have hopeless aerodynamics. The best sportsbikes are still almost double the coefficient of drag of a decent car.

So consider this.

CAR = Subaru Vortex
ENGINE = 15hp stationary diesel

Air density = 1.2 kg/m3
Coefficient of drag = 0.29
Frontal area = 1.3x1.7 = 2.2 m2
Specific fuel consumption = 250g/kWh

Estimated maximum speed = 85kph
Estimated fuel consumption at 80kph cruising = <4L/100km.

Marry the engine to the trans in the same way as they do on the above website, with a CVT - this allows the engine to sit on virtually optimal rpm in any gear, and the CVT will cause the car to slow down when going up hills and speed up on the other side.

The reason I'm thinking this is the aerodynamics of the Vortex are about the same as a motorbike. Sure, it's pulling a lot of mass so acceleration will be poor, but in the future, when there's no petrol at the pump, any vehicle that gets you 100km on $10 worth of supermarket veggie oil at 80kph will be pertty darn appealing!

Its not just the Vege oil tho is it? My understanding is that the main cost in making Biodiesel is the other ingredients (such as menthanol). Still works out a fair bit cheaper than regular pump diesel tho

You're spot on. Biodiesel's made by mixing alcohol (20%) and vegetable oil (80%). This produces biodiesel and glycerine. You wash your hands with the glycerine and then put the biodiesel in your car

BTW I'm not driving Subies any more; I'm driving a Peugeot 405 SRDT on 100% biodiesel, fuel purchased from the pump at SAFF (at Parafield Gardens) for about $1.30/L. For me it's not about the price, it's about not contributing to the end of the world 8O .

Anyhoo, diesel engines CAN be operated on straight vegetable oil (SVO). The first diesel motor ran on peanut oil! The major problem is viscosity of the fuel (veggie oil is a bit too thick), but a simple inline heater seems to sort this out. There are numerous websites by people running all sorts of engines on SVO.

You gain efficiency in going to diesel (specific fuel consumption is much better than a petrol engine running on straight ethanol), and the aerodynamics of the Vortex are too good to miss. Seems to me like an awesome combo!

Does anyone know what sort of losses there are in the drivetrain? I haven't yet factored this in...

I don't know the figures but I know theres not much lost if you leave it in front wheel drive.

I've now factored in rolling resistance, drivetrain losses, auxiliary power losses (eg alternator) and the fuel efficiency is nowhere near as good (nor is the top speed as high). I think I'll stick to my Peugeot!

Mind you, a diesel motorbike has lots of potential. Bikes are quite poor aerodynamically (a car is better) but as bikes have very little rolling resistance, they can potentially achieve quite good economy. Some people in Europe have put little diesel motors in bikes and get 1.5-2L/100km...

Hmmm... Project...

interesting concept...the vw diesel in a sube...but it would need completely different gear ratios wouldn't it ? for best results......

is vw diesel a front wheel drive ?

The 1.9 TDi is from the Golf and Polo, both of which are FWD (hatchbacks).

Regarding gear ratios, that's a matter of figuring out the torque/rpm relationship for the engine and picking an "optimum speed" in each gear.

Diesels have a much narrower power band than petrols. My Peugeot comes onto boost at about 2000RPM and is totally spent by about 3500. Eventually CVTs will become more common but until then, it's lots of gear changes...

Actually, it's not that bad - you're cruising at 80 in 5th, doing about 2000rpm, and you're already on boost so if you need to overtake, you just do it - no need to change down!

Re end of the world: It might not use any Oil based fuel, but would the emissions be really bad?

The emissions of new common-rail diesel engines are much better than the traditional diesel engines. They also burn cleaner than petrol, meaning you put out almost all CO2 and no CO (CO being the bad one). If you run a diesel engine optimally (eg in a CVT and/or hybrid electric arrangement) you should minimise the emissions also.

With biodiesel and you get a small increase in NOx (bad) but a significant reduction in particulates (particulates are the nastiest thing, healthwise, about diesel engines).

The most exciting thing with biofuels is that you potentially close the carbon cycle, meaning the car behaves - ecologically - like a herbivore (i.e. it "eats" vegetable oil, and "breathes out" CO2 - then the CO2 is absorbed by the next crop of vegetable oil, and so the cycle continues).