richardd Posted July 22, 2008 Report Share Posted July 22, 2008 I have recently bought a 2006 A8 W12L and am considering converting to LPG. Greenfuel are able to fit a BRC Sequent system and the man-maths seems to make sense. I appreciate any advise that people have before I go ahead. I have read many horror stories as well as comments from people who have been happy, but I haven't seen any for the W12. I didn't buy the W12 expecting decent fuel economy but if there is a way of reducing the running costs then "why not"? I guess my major concern is that LPG seems to run hotter than petrol, the W12 is so compact that cooling may be a problem. I believe that the con-rods are also much thinner on this engine, would the additional heat be a problem there? Thanks in advance. RicD Link to comment Share on other sites More sharing options...
LostKiwi Posted July 22, 2008 Report Share Posted July 22, 2008 I have LPG on my old Range Rover and its great. My son in law has his converted too. I'm now just waiting for A8Parts to get a 4.2 LPG equipped car in so I can whip (er buy) the LPG kit out of it. The increased heat thing is more an issue for older engines where the valves and seats can be a bit 'soft' and prone to burning valves. Not an issue with Audis as the valves and seats are as hard as nails. Link to comment Share on other sites More sharing options...
treetotreef Posted July 22, 2008 Report Share Posted July 22, 2008 Is your W12 an FSI engine? if so it may be worth checking out this thread from another forum... AudiWorld Forums: Re: FSi Conversion to LPG & lpg_and_fsi_gdi_direct_injection_engines According to these, switching off the direct injectors completely could cause them to clog up and/or overheat. Running some fuel through them seems to be the answer, they quote 25% on those links, but of course this would mean your savings would also be reduced by a similar amount Link to comment Share on other sites More sharing options...
MICKPSU Posted July 22, 2008 Report Share Posted July 22, 2008 Thats a brave move. I would probably guess you will be the guinea pig for us W12 drivers as I dont know of any other in the country. What about the warranty? I have a 2005 W12 with an Audi warranty and maintenance pack running until 2010 or 75K miles (whichever the sooner). Surely your warranty will be void if you LPG the engine? Link to comment Share on other sites More sharing options...
craigyb Posted July 22, 2008 Report Share Posted July 22, 2008 Warranty is only 3 years, service and maint is 5 years on the W12's Link to comment Share on other sites More sharing options...
dalep Posted July 22, 2008 Report Share Posted July 22, 2008 Warranty is only 3 years, service and maint is 5 years on the W12's My 05 W12 has full bumper to bumper Audi warranty till April 2011 And yes, I would assume fitting LPG will void this. Let us know if you make any progress on this, I currently run 2 Volvos on LPG (factory fitted) and it does make a big difference on the wallet. The main thing to lookout for, there is less MPG than on petrol and the price of LPG is gradually creeping up and up. In 2003 when I got the first V40, it was 29 pence per litre. Now its crept up to 60.9 here on the south coast!!! If it creeps up much more, it will be hard to see much of a payback on the cost of the installation in the first place. Also, one final point, on a large engine like the W12, It is VERY hard to pipe enough gas into the engine at high revs, so the system normally reverts back to petrol at this point. If you drive the W12 hard, you would still use quite a bit of petrol! My 2 pence worth!! Dale Link to comment Share on other sites More sharing options...
craigyb Posted July 23, 2008 Report Share Posted July 23, 2008 I think you might get a shock in 2009 I though the same, but the warranty is not the same as the 5 year service and maint plan, it is seperate, so unless you have specifically bought an extra 2 years of warranty, I would check with Audi UK. My 05 W12 has full bumper to bumper Audi warranty till April 2011And yes, I would assume fitting LPG will void this. Let us know if you make any progress on this, I currently run 2 Volvos on LPG (factory fitted) and it does make a big difference on the wallet. The main thing to lookout for, there is less MPG than on petrol and the price of LPG is gradually creeping up and up. In 2003 when I got the first V40, it was 29 pence per litre. Now its crept up to 60.9 here on the south coast!!! If it creeps up much more, it will be hard to see much of a payback on the cost of the installation in the first place. Also, one final point, on a large engine like the W12, It is VERY hard to pipe enough gas into the engine at high revs, so the system normally reverts back to petrol at this point. If you drive the W12 hard, you would still use quite a bit of petrol! My 2 pence worth!! Dale Link to comment Share on other sites More sharing options...
richardd Posted July 23, 2008 Author Report Share Posted July 23, 2008 Many thanks for all the replies... I am waiting for a response back from Audi on the warranty issue. I suspect "engine failure" could get a bit pricey. The cost to change to LPG is around £3K but at 15-20,000 miles a year it should still pay back - not sure what it will do to resale value though, I guess that depends on fuel prices in a couple of years time. I will post the response I get from Audi. Link to comment Share on other sites More sharing options...
alera Posted August 14, 2008 Report Share Posted August 14, 2008 (edited) Dupe............. Edited August 14, 2008 by alera Link to comment Share on other sites More sharing options...
alera Posted August 14, 2008 Report Share Posted August 14, 2008 (edited) Warranty is only 3 years, service and maint is 5 years on the W12's Craig in my experience what you are saying on the maintenance and warranty is not correct. I recently had this conversation with Audi when my 3 years was up and they confirmed that, depending on the package sold at the time A8s with the 5 year service and maintenance pack do have full warranty cover for the duration. If it’s got the full 5 year package there is no need to extend the warranty. Extended warranty is available for cars with only 3 year warranty no maintenance for around £1400 a year apparently (up to 5 years 80,000 miles I think) I have this in writing from Audi UK to this effect and also had the agreement transferred over to my name. It took a few weeks to sort out and trace the records but only because my car was first registered and owned by Audi UK. There is a fair bit of confusion about this. I would recommend you go into your local dealer, speak to someone senior and they will properly get the bottom of the warranty situation for your vehicle. Its worth mentioning that almost all the W12s that were sold in the UK for the first couple of years after its launch came with the 5 year maintenance package; my dealer had never seen a car from this era without it. On the lpg issue, personally I think its complete madness to convert a w12 to LPG. Yes fuel is expensive but if you are worried about the economy you don’t by a w12....If the engine goes on a w12 it’s the end of the car in the current climate. End of story. Edited August 14, 2008 by alera Link to comment Share on other sites More sharing options...
A8 Doc Posted August 14, 2008 Report Share Posted August 14, 2008 On the lpg issue, personally I think its complete madness to convert a w12 to LPG. Yes fuel is expensive but if you are worried about the economy you don’t by a w12....If the engine goes on a w12 it’s the end of the car in the current climate. End of story. Completely disagree. As you don't run LPG you don't really know the systems. I properly setup system that is sequential will be fine. I run an D3 A8 4.2 Quattro with 40k on LPG now. No problems in the slightest. Audi Technician remarked how well the car ran and how clean the oil was. The engine failing on a W12 is just as likely under petrol or LPG to be fair unless it is fitted by a complete idiot. Link to comment Share on other sites More sharing options...
A8 Doc Posted August 14, 2008 Report Share Posted August 14, 2008 P.S. What's the Maserati like? I have been so tempted by one of those? Link to comment Share on other sites More sharing options...
alera Posted August 14, 2008 Report Share Posted August 14, 2008 Love the 4200. Noise from the v8 ferrari enigine is immense. Its been a very good car so far. It just seems like vandalism drilling holes and messing with a w12 engine to be honest.... Link to comment Share on other sites More sharing options...
A8 Doc Posted August 15, 2008 Report Share Posted August 15, 2008 Lovely car. Thats on my list next I think. It's only really in the inlet manifold. Only fuelling systems. Worth it for the savings. Link to comment Share on other sites More sharing options...
alera Posted August 15, 2008 Report Share Posted August 15, 2008 Wasnt someone else saying due to the engine capacity on the 12 it is near on impossible to get enough lpg in there if the cars driven with any gusto at all though ? The cost of the conversion, if the system ends up reverting to petrol every time you put your foot down is it really worth it ? Also LPG seems to be going up in price at a fair rate as well. Seems like an exercise in futility to me on this particular car... I dont do many miles but with these cars its not the fuel that is the problem even at current levels. Its the depreciation that costs the real money. You can pick up a top of the range v8 supercharged range rover sport, 3 years old 36,000 miles for around 20K this days. £75k plus new....... Link to comment Share on other sites More sharing options...
Figure11 Posted August 15, 2008 Report Share Posted August 15, 2008 Seems like an exercise in futility to me on this particular car...I dont do many miles but with these cars its not the fuel that is the problem even at current levels. Its the depreciation that costs the real money. You can pick up a top of the range v8 supercharged range rover sport, 3 years old 36,000 miles for around 20K this days. £75k plus new....... When put into this context the fuel savings pale into insignifcance. I think I read on the general form that depreciation, maintainance and fuel cost a RS6 owner £13 a mile on the sale of his car! Saving 10p per mile on fuel costs wouldn't make much of a dent in that. However, 23500 X 10p = 2.3 k per year. Thats what I am saving now..... Mike Link to comment Share on other sites More sharing options...
alera Posted August 15, 2008 Report Share Posted August 15, 2008 (edited) If you do the miles and it will work well on the car you have its worth doing. However I would question how well lpg would work with the w12 engine after some of the things I have read.... Its an enourmous gamble to take with such an expensive engine and given the fact its almost certainly still in full warranty.... Edited August 15, 2008 by alera Link to comment Share on other sites More sharing options...
dalep Posted August 18, 2008 Report Share Posted August 18, 2008 I took a long hard look at this as I run 2 other cars on LPG BUT a few things put me off... Looking at how it is done on other 12 cylinder engines (BMW and JAG) it might not be as straight forward as some LPG installers think. On the Jag 12 cyl conversion they actually install what is in effect 2 complete systems, both sharing a common fuel tank, OR they can be fitted with 2 tanks in tandem, COST - between 3 and 4K ouch! The installers I found that offer one system, are actually driving 2 sets of injectors from 1 ecu and when I contacted the ecu manufacturer, I was told quite politely that it was a no no and the ECU warranty would be voided - great! Lastly, the injectors will most likely not fit under the aluminium engine cover so you will have to ditch that, looking under the hood of a W12, is there really the room to mount 2 mixers etc etc?? Also, I know there are A8's that have been done (just not W12's), but due the the Aluminum chassis, there are SO many things that can go wrong in the future if EVERY nut / bolt / screw is not correctly fitted, not sure I would trust them. As pointed out, it WILL void the warranty with Audi (I checked with AUK), the LIST price for a W12 engine is 17000 or 11500 on exchange!!! Chances of picking one up at a breaker, probably nil... On that note, I wouldnt consider it for a second, I love my W12 too much - anyway, where would I put the fridge :grin Dale Link to comment Share on other sites More sharing options...
richardd Posted August 19, 2008 Author Report Share Posted August 19, 2008 I appreciate all your responses, the argument certainly is convincing to avoid LPG on the W12. The risk is too high compared with any savings especially as it is still under warranty. You are right about depreciation, mine was less than two years old when I bought it from an Audi Dealer with only 9K on the clock and it had depreciated over 75% from new price. There still is along way to go, but the car was effectively new for the price of a new A4 2.0FSI ! Thanks again. P.S. The Fridge argument was most convincing - not that mine has a Fridge yet (anyone have a spare A8 Fridge to part-ex for my Ski-Bag?) Link to comment Share on other sites More sharing options...
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