The dip in MPG is minimal running on LPG - the D isnt exactly economical as it is, so wont make much difference (circa 5% loss of MPG).
We've just done some quick maths - Say, the installation on a DeLorean (DIY) costs £1000 including certification.
Ok: Unleaded petrol - 1,000 miles @ 20mpg = 50 gallons @ £3.90 per gallon = £195
LPG - 1,000 miles @ 19mpg = 52.63 gallons @ £1.90 per gallon = £100
So therefore, for every 1,000 miles, you will save £95 in fuel (about three tankfulls in a DeLorean). It will therefore take you 10,500 miles to recoup the £1,000 outlay. Obviously, if you get a professional company to do it who charges £2,000 then it will be more like 20,000 miles. Flopsy and Sorbet clocked up about 15,000 miles between them last year - and I would have used Flopsy even more if she was cheaper to run.
On top of this saving in fuel costs, you can also have the satisfaction of knowing you havent chucked loads of pollutants into the atmosphere (and no I'm not a raving tree hugger!!! :lol: ) The only downside I can see, is that you cant take an LPG car through the Channel Tunnel, so we'd have to use a ferry
At the end of the day, we want to use our classic cars more often, rather then have them tucked away as garage jewellery, coming out for the occasional Sunday jaunt.
I dont see what the problem is running LPG? Its only a fuel, and one that is compatible with the petrol internal combustion engine, and one that produces less pollutants, is cheaper to buy and has a lower level of duty (Jan, LPG cars are taxed even less if they are newer as since 2001, new cars in the UK have been taxed according to their CO2 emissions). Deans reason for looking into LPG is that it is cheaper to buy, and as he goes into London alot, means he doesnt have to pay the congestion charge (although this may be up for debate .... )
I was talking to some friends down south the other week, they said they could remember Taxi's in Stevenage running LPG in the late 60's, so its not as if its some new fangled idea.
I also got chatting to a guy at a petrol station one day, as he was filling a very nice early Jaguar XJ up with LPG. I asked if he had any problems or running issues. He said that the car ran fine, there was no noticeable difference in MPG or performance. He also said, that if it wasnt for LPG, he wouldnt be able to afford to run a Jag.
As for cutting the car, that wont be as extreme as some of you may be thinking. You would need to anchor the tank through the spare wheel well, and we have come up with a way of having a very discreet external filler, which you wont even know its there.
All that needs to go down to the tank is one 8mm copper tube for the gas filler, and a 6mm copper tube that goes to the engine. These exit through the 1 inch round vent hole in the case of a torrodial tank. So the worse modification there will be for a donut tank would be 2 mouting holes for the bolts, and a 1 inch vent hole in the bottom of the spare wheel housing - and these can easily be repaired with fibre glass should the system ever need to be removed. Therefore the value of the vehicle should not be affected (and we dont intend selling our D's anyway, so that wouldnt matter to us).
If you are concerned about any additional engine wear running on LPG, engines that were designed to run on unleaded should be fine. But, if you have any concerns, it is very simple to add a small oil dropper unit that would normally be fitted to cars that were designed to run on leaded (like my Rapier) as it gives a bit of extra protection (a one litre bottle would last months and costs pennies).
As a side note, Practical Classics magazine are very interested in LPG and other alternative fuels, and have asked me if they can run a feature on it when I start the conversion on my Rapier. I guess in an ideal world, we would be doing Rapey and Sorbet at the same time
Obviously, we havent completed the conversion project yet, so the full results are yet to be known. However Phill is very keen to convert Sorbet (as I am on Rapey) and is looking forward to completing the project as soon as is possible.
No doubt, he will post his results in due course
Regards,
Claire & Phill