Audi A2 / VW Lupo 3 cyl. 1.2 Turbo Diesel

You realize that 'over "the pond"' is relative, don't you?

Can you describe your plans more fully? (I'm just interested, seems like an unusual project!)

It comes down to money. I am not against putting a rotax or other small aviation engine in a Zenith 701. Many others have put automotive engines in airplanes put have to gear the prop down. To get a small automotive engine to put out the hp and torque you have to turn lots of RPMs. The automotive light wieght diesels however have enough hp and torque at the lower rpm. Also the engines sip fuel versus their gas cousins. Even though the power plant would weigh more than an aviation engine ie Rotax 912 you could easily put smaller fuel tanks or carry half the fuel. The reason I contacted this board was in hopes that somebody would know of a good salvage yard (breaker), good rebuilder, or a parts dealer that I could get a new in crate engine. Diesel engines have gotten lighter, more powerful as well as goes further on a liter of diesel. This in part to common rail fuel injection as well as the ECU (electronic control unit). Once again since we in the "States" dont'have these cars, VW Lupo or Audi A2 or the 1.2 liter 3 cylinder turbo diesel power plants I am turning to you all for assistance. Thanks, Bill

Are you sure that using an engine that isn't sold in the US is a good idea? Getting parts and significant support may be a problem.

You may want to check reliability of the engine components, and what the ECM controls. In some vehicles the ECM does both the engine and the transmission (if it is an automatic), and that could be an issue--you'd have to get a manual transmission engine/components.

Were this me, I'd want the entire car, so I can take all the little bits and pieces (nothing like needing that unique valve that mounts on hte firewall and costs a billion dollars...) as they are needed. Not sure what your budget is but it may be possible to import one as parts? (May be, but I"m not sure...)

Your project does sound interesting, however.

Given that the 1.2 Lupo/A2 were 3L cars and fairly specialist I would pretty much guarantee that the ECU controls more than the engine. IIRC, they had fairly clever automatic gearboxes that allowed them to achieve good mpg figures. Thinking further, I believe you can't run one of these engines without the instrument cluster from the same car. So really to use it in an aero application it would need a custom ECU

If the OP is intent on getting a small diesel then perhaps the 1.4 3 cylinder engine would be a better option as it is still economical but can be chipped up to around 100bhp

However, the 1.4 is significantly heavier than the 1.2 - a distinct disadvantage for an aero application.

Yep, that was what I was thinking... Because it is such an unusual engine setup finding stuff for it may be next to impossible. Building a custom ECM (ECU, or whatever you want to call it ) is quite possible, but not trivial by any stretch of the imagination. Were I to have a commercial customer come to me for something like that (I do a lot of custom stuff of a similar nature) I'd probably tell them they are looking at 6 months at least, and a six figure (US$) + price tag.

The real answer might be to see if the engine management system (ECM/ECU) from another three cylinder diesel that is less integrated might be grafted onto the engine of choice. Say, take the one used on the 1.4 and stick it on the 1.2. That would require some (perhaps minor) retuning of fuel delivery rates, but may work just fine otherwise.

Diesel engines are actually easier to control than a gas engine--you don't worry about ignition timing, only fuel delivery and timing. You can even make it simpler by not worrying about fuel econonmy and just shooting in fuel as needed without worry as to whether it is the best amount or not. THis would result in some 'black smoke' from unburned fuel that would result from over fueling (low RPMs, high throttle settings for example) but that may be a minor problem.

Correct. The engine ECU is coded to the immobilizer in the cluster. It can be disabled, I believe, but that's a specialist task. Really you'd want to find a crashed car with the 1.2 TDI, take all the bits you need, and get rid of the rest. There would be all sorts of stuff to sort out, like fooling the ECU it has a clutch and brake switch to prevent limp-home, for example.

But it's a cast iron block rather than alloy, so as someone said, it's much heavier.

I'll bet a lot of the system is the same with different software, so taking the system from a A2/Polo/Fabia 1.4TDi would be even harder.

It's a very interesting idea, but not sure it's the easiest route to take. Here's a thought: how about the industrial engine range? They sold the 1.9 TDI with the VE injector pump (and at one point you could get some *very* useful literature on it), so maybe they do the 1.2?

I looked into the industrial engine route on the VW and the only one I could find is the 1.9 which is too heavy. Could you explain "the like fooling the ECU it has a clutch and brake switch to prevent limp-home, for example." Thanks, Bill

IIRC there's 2 brakelight switches, and a clutch switch. The clutch switch could be ignored, probably, but with the brake switches you need to make sure the ECU doesn't think there's a fault. I believe it compares the 2 switches, and if one is different, throws a check engine lamp. This may or may not reduce power- I can't remember. I do know that a very common cause of the check light is a blown brake bulb....

You'd probably be best getting the pedals and wiring to be sure, as there's the electronic throttle sensor to get as well.

I saw your post in uk.rec.cars.vw.watercooled too. I think you'll have trouble sourcing one from a breakers. I didn't even know the A2 came with the 1.2, and Lupo 3 litre cars with it are very rare: I have never seen one. Plenty of the 1.4 iron-block, but that probably doesn't help.

One thought- apparently the toyota Yaris has an alloy-block diesel. That might be easier to find. Seems to have had an appetite for head gaskets though

as has the alloy-block version of the Peugot/Citroen TUD, it would seem :-(, but it could be worth a look?

You could try asking at

in the forums.

Humm, putting a brake pedal on an airplane... That's interesting!

(OK, full sized planes do have brakes, but I don't think I've seen brake lights on any. )

Haven't you heard of "air brakes"? No, what he is talking about is I need to consider "fooling" the ECU that all is well with the brakes and clutch systems, even though they don't have those systems installed. Keep it coming. Bill

Drag chute! Just like on the fighter planes.

I keep wondering if this engine might be used in any industrial equipment such as fork lifts?

I don't know about the 1.2 but the larger 1.6 or 1.9 does have an industrail VW engine. VW has an industrail engine page however it is cast block and it weighs too much. Bill

The concept should work. Only the designcriteria for aircraftengines and materials requirements may differ from car engines in general. Aircraft have higher redundancy in general than cars. Sensors and avionics have a factor

1. Audi does not provide this in their motormanagement.
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