Project : LPG Conversion on 5.3 V12 XJ-SC

By Roger Farmer

Published: 6th December 2017

Converting a classic Jaguar to LPG is not a decision taken lightly. For some owners it offers significant reductions in running costs and emissions, while for others originality remains paramount. This article documents one owner’s experience of converting and living with an LPG-powered XJ-SC Cabriolet.

I recently converted my 1986 XJ-SC Cabriolet to run on LPG and felt it would be useful to share my experience with other Club members.

I have been using LPG on other vehicles since 2008 and, over that period, have encountered no problems attributable to the fuel itself. Including the cost of installation, my overall fuel savings across multiple vehicles have exceeded £12,000.

The conversion on my XJ-SC was completed in August 2017 and has performed reliably since. An 80-litre LPG tank was installed in place of the spare wheel, which required relocating the battery to the right-hand rear wing.

Running Costs and Practical Benefits

One of the primary attractions of LPG is long-term fuel cost. My XJ-SC typically returns around 17 mpg on short journeys. With LPG priced locally at approximately 60p per litre, this effectively halves my fuel costs compared with petrol.

There are additional financial considerations. Road tax is slightly cheaper,