Since January 2012 the petrol prices went up a lot and reached 1.50 euro/liter or 7.50 U.S. dollars per gallon. This is kind of a local record and the worst thing is that the experts expect it to increase even more this summer.

That's why I decided to install LPG on my XJ8... I've always been against converting the engine to work on gas, because it brings nothing more than troubles, but since the price of the LPG is 0.50 euro/liter (3 times cheaper), I realized it's worth it.

I can't post a lot of experience because it's been only two days since I've got the car back from the workshop, but the torque and the power of the engine seem to be absolutely the same (already tried max speed and reached 235km/h on LPG), the acceleration is the same and the fuel consumption is absolutely the same - 16.5 liters / 100km urban driving.

The LPG system is Italian - Landi Renzo which is one of the best on the market right now. The total cost went up to 1400 euro (1850 US dollars) and it took 5 days for full installation. The LPG container is for 60 liters of gas and it's located in the trunk. It's "eating" a lot of the trunk space, but I can handle it The car always starts on petrol and it runs on it until it reached both 40 degrees of coolant system and 1800 RPM - than it turns to LPG automatically. This happens without any signs - kicks or loss of power.

Here are some photos of how the engine bay is looking now:

This is the control unit inside the car. With it I can check the level of the LPG in the container and switch between gas and petrol:


This is the engine bay:







The only problem I have with it up to now is a random "Restricted Performance". I'm sure that tomorrow morning the specialist from the workshop will be able to fix it, but unfortunately my new OBDII reader still haven't arrived.

I will post more information in the future after I test the car in different conditions.

 

Wow! You have me thinking about this now. Its a shame that cars dont already run on gasoline vapors.

 

Why would you install the switch on the passenger side?


I always wondered what happens if you get rear ended with a system like that.

 

He has a RHD XJ8 so the switch is on the correct side.

It is a good idea though, it is something I intend to install at some point. I'll have a tank in the spare wheel well so won't lose any boot space.

 

So you have 60liters of LGP + 88liters of petrol (the factory tank) in your jag?? That much weight is not going to help fuel mileage very much. Also you were and are getting 16.5 liters / 100km, that is not good mileage (15mpg for the Americans here) - if you are really keen on saving fuel $ it might be worth investigating why your jag is getting such low mileage. Mine gets about that in aggressive stop-and-go NYC traffic.

FYI, Bulgarian fuel is not so expensive; 98ron petrol in Israel is $2.75-USD per liter!

 

Nice post and thanks for sharing.
I guess I'm surprised there aren't many more posts of this type with the way that fuel prices are going?

Haing said that the bulk of our members seem to be from the US and enjoy much much lower prices at around £3.16 per gallon, compared to UK £6.55 per gallon ( based on diesel )

I see however, that thats enough get people worked up at rising prices, so there may be more posts of this type soon I would think.

 

@estillian,

Just below the dash vent, there is a four position rotary knob. There is also a push button with the image of a car. What are their functions?

 

It depends... 60 liters + the LPG container will weight about 80kg. So this is like full tank. I don't need to have the petrol tank always full so I keep it on half. That's about 40kg over the weight of having the car with full tank and I don't think this is much It's like having a nice sexy blond sitting next to you while driving


Having in mind that on highway it gives me 10/100 l/km I don't think it's so bad. 16.5/100 for urban seems to be normal (have in mind that the 3.2 has lower mileage than the 4.0 engine). Actually the first time I had refueled my Jag I was terrified by the fuel consumption. I did almost everything that could be related to the low mileage - and no change until now. Everything about throttle body (cleaning, connections, etc), the MAF is working properly, the air filter is new and clean, the part load breader is clean, new spark plugs (NGK), new gaskets... I don't know what else could cause an increase of fuel consumption?!


Yeap, maybe you are right, but the average salary in Israel is not 300$ I get 1200$ per month and this is one of high paid places in the IT sector So I don't think you can compare countries. My mom is a surgeon for more than 20 years and her salary is 400$ per month - said story. Now do a simple math and try to get idea how expensive is the petrol for bulgarian standards actually

 

Stu I wanted to have the tank exactly there but the problems are two:

1. I couldn't install tank that it's big enough to feed the beast The biggest LPG container that could fit in the spare wheel space was about 48 liters and I believe this is to less.

2. If you put the LPG tank there you have two options:
- Drive without spare wheel and while driving outside the city I think it's a bad idea!
- Leave the spare wheel in the trunk... and the space that the wheel needs is much more than my 60 liter LPG tank

The rotary knob is the low beam regulator. You can use it to move up and down the front lights beam... for example if your trunk is to heavy (a lot of luggage and 3 persons on the back seats) the front of the car will rise up and your lights will dazzle and blind the other cars. Than you can use the switch to turn the low beam down. The default position always should be the highest set (in the XJ case this is the zero).

The other button is for opening the trunk. The image is a car with an opened trunk

And if you are curious enough - the other think, below the the buttons, that is inserted in the glove compartment is a Cobra radar detector I hide it there when I don't use it.

 

And this adjustement is mandatory in most of Europe. US spec cars don't have it.

 

I forgot to mention - there is another option for different type of installation. Instead of LPG there is a system working on Methane (another type of gas). It has some advantages and a lot of disadvantages:

1. The price is incredible low. It's complicated to talk about price per liter because the Methane is calculated in kilograms but imagine that: run a XJ8 in urban with 5-6 U.S. dollars for 100km and for about 3-4$ for 100km on highway

Maybe this is the only advantage... if we forget about the fact the you can make a diesel engine work on Methane as well... BUT! Here comes the problems:

1. The entire system + the installation are more expensive than the LPG. It would cost about 2000 euro (2650$). Having in mind the price of the Methane it's not such a big deal.
2. Massive loss of power... A specialist told me I would have about 60%-70% of the total power of the car. Forget about the nice torque of the XJ V8 engine, forget about speeds over 180km/h.
3. Huge weight of the Methane tank. The fully loaded Methane container which will be enough for 200-300km run is about 300-400kg. Believe me - this is ruining your back suspension for an year. There is some new tanks made of carbon but the price for a normal tank would be about 1500 euro (+ the previous price I mentioned for the entire installation) and it will weight 200kg
4. Still there are not enough gas stations that offers Methane for cars. Here in Bulgaria we have about 10 stations in the capital and 10 more outside, mostly in the big cities. It's a good option for a urban car, but if travel a lot - not such a good idea. And the only place I've seen Methane stations outside Bulgaria is the homeland of gas systems - Italia
JKo could tell if there are any Methane stations in Finland for example?!

I don't think Methane is a good option for Jaguar. After all - this is a luxury car with style... and putting such a piece of technology in it would be like changing it for a Russian Lada

P.S> Methane systems are the most popular thing among taxi drivers They don't need torque or power, they don't care about quality of suspension, they drive only in the city and they definitely want to run as cheap as possible In the past two years the Mayer of the capital decided to invest and converted all the city buses to work on Methane (all the buses are Mercedes with diesel engines). The reason for that was the low price they could offer for tickets as well as the ecology - if you compare diesel with methane, the gas is much more clean for the environment.

 

Yes indeed, and here's one

In Finland gasoline is getting close to 1.7€/liter ($8.48/gallon), and LPG is not availabe widely enough to make conversions feasible. There is however cheap(er) E85 available for about 1€/liter (called RE85, made out of biowaste)... it does decrease mileage, but the price is so much cheaper that lots of ppl are converting their cars to FFV/flexifuel to run with it. Some just blend it with regular gas and run with E30-E70 blends without any modifications. I'm thinking about doing this myself... I wonder if there's anything that might go wrong with the increased amount of ethanol in the XJR, like the tank, fuel pumps, fuel lines etc?

 

There is a great deal of interest in running E85 in some tuner circles. The big deal for them is whether the fuel pump is E85 certified. That would imply that there would be an effect on your fuel system.

 

I think it's marketed as CNG..? There are some, maybe a dozen or so. Most of them are near Helsinki in southern Finland.

 

Thanks. As JKo noted, it is not on the US cars. But, it would be a great piece to use for yet another of the always necessary additional switches

 

I would suggest reading about how much sulfur is in this E85... as much as I remember from talks with friends from Russia they told me that this fuels are very high-sulfur. Be careful with the nikasil in your engine...

 

Don't worry I've not gone into this blindly I'd researched it, just haven't got round to having it done yet.

It is possible to put a tank in the spare wheel well it will also be of ample size. A space saver spare wheel, as supplied with many XJ8s, can be placed on top of the tank without causing any problems in the boot. I've seen this done on many cars including XJ8s.

 

Maximum sulfur content allowed in any fuel sold here is 10mg/kg (ppm), so it shouldn't be a problem. I think this is an EU wide regulation. Fuels sold in Russia may have higher sulfur content.

 

I did a bit of searching on the CNG (compressed natural gas, mostly methane I guess)... there is one station selling this quite nearby, and a conversion for an 8 cylinder car would cost something like 3,000-3,500€. Savings in fuel costs would be around 1,000€ per year (with my yearly mileage). And the trunk would look something like this (pic is from a Chrysler 300C):

http://oragas.fi/images/stories/pa160314.jpg

Not quite convinced.

 

The pic didnt work for me, son.