LPG conversion for 462 CI Riv

[Bad Boattail]

Hello,

In the Netherlands we are paying the highest price for petrol in the world, and a lot of us are using LPG (Liquefied Petroleum Gas) to drive our classic cars. Why?

1st: Petrol is about 1.18 Euro a litre, that's US$ 4.46 for 1 US gallon. LPG costs 35 Eurocents a litre, that's US$ 1.32 for 1 US gallon.....that's a big difference?!

2nd: Our roadtax is very high, and depends on the weight of the vehicle and type of fuel.
A car with the same weight as my 73 Riviera will cost you about US$ 1200,- a year in roadtax when it's using petrol for fuel.

On LPG, a car with this weight will cost you about US$ 2400,- a year in roadtax (but LPG is much cheaper, so it's paying off when you drive a lot)

Thank God we have a roadtax-exempt law for cars older than 25 years, so it's even cheaper to convert our big gas guzzlers to run on LPG.

All my cars are converted to run on LPG (running them on petrol still is possible with the flick of a switch)

Here's a picture of my 118 litre LPG tank:

<img src="http://pic7.picturetrail.com/VOL188/1011648/1886710/23582601.jpg">

Don't let that NOS sticker fool ya...:)

Filling up this tank is done through a nozzle, placed under the licenseplate-holder, next to the filler of the fueltank. In the Netherlands it's no problem finding LPG stations, nearly everywhere they're selling petrol, there's a LPG fillingstation.

<img src="http://pic7.picturetrail.com/VOL188/1011648/1886710/23582594.jpg">

Inside the car I have this switch with 4 green and 1 red LED's, LPG is liquid so a float-assembly is used inside the tanks. When you're all filled up, the 4 green LED's will light up, depending on how much fuel there's left after driving 3, 2 or 1 green LED's will light up. When there's less than 15 litres in the tank, the red LED will light up. (Shown on picture) When the switch is in the position on the picture, I can drive on LPG. When I switch it to the right, the car will run on petrol.

<img src="http://pic7.picturetrail.com/VOL188/1011648/1886710/23582607.jpg">

The LPG will enter the enigecompartment under a pressure of 120 PSI and it will pass through the convertor. This convertor is warmed up by the cooling-system and the liquid LPG will change into gas.

<img src="http://pic7.picturetrail.com/VOL188/1011648/1886710/23582622.jpg">

The gas is mixed with air at the mixer inside the airfilter

<img src="http://pic7.picturetrail.com/VOL188/1011648/1886710/23582616.jpg">

This is what the engine looks like with the convertor and the mixer is place.

<img src="http://pic7.picturetrail.com/VOL188/1011648/1886710/23582609.jpg">

The LPG tank in the back has a device that is opened by a 12 V pulse coming from the ignitioncoil, so when you have an accident with the car, the LPG tank will be closed the very moment the engine stops running. It's a very safe kind of fuel, petrol is even more dangerous. There's a safety valve inside the LPG tank that releases the fuel when the pressure inside the tank gets to high (when the car is on fire) I've seen a fire in a garage where a LPG powered car went up flames, every 30 seconds the safety-valve opened up and there was this big blow-out of LPG. The fireman I spoke to said that he was more afraid of cars on fire with petroltanks, they can always explode.

Well, hope you liked my explanation why it's cheaper for us to run on LPG in the Netherlands.


Erik.

[custom sky]

Eric that's a cool display you did. How much does it cost to convert to the LPG system? How many miles to the gallon or liter do you get compared to the petrol? Also what kind of performance change is there? Do you have less power or about the same? Does the LPG have a similar octain rating as the Petrol? Do you evan use an octain rating like 91 octain? One last question did you have any problems tuning the carb to run on LPG? Change the jets and such? Give us the scoop.

[Bad Boattail]

Hello Jason,

The conversion in 1996 for my Riviera was 3000 Guilders, the US$ was at 1.90 Guilders at that time. So lets say about 1500 US$.
But all th ework was done at a garage, they also handle all the paperwork, and pay for the test that a new system has to perform. In my Caprice wagon I installed everything myself, the DIY kit was about US$ 600,- , the tank was another US$ 200,-
The test and paperwork was another US$ 100,-
After adding all the odd bits and parts together, the DIY was around US$ 1000,-

There is about 5% loss of power, but the cheap fuel is making it acceptable. We are running 98 octane petrol here, but the numbers are not similair to the ones in the USA. There's no need for tuning the carb at all. LPG is a very clean fuel, and there's less friction in the engine compared to running it on petrol. But the heatrange is higher, so the engine gets a few degrees warmer.
1 Big advantance of LPG is it that you can run 13:1 compression without any trouble.

The fuelconsumption is a bit higher on a 350 engine, but for a 462 CI BB there's not much change to notice. I'm using an average of 33 litre every 100 KM on LPG.

But Big Bufords like to run on LPG............ 5% loss of power??
Check this out:

<img src="http://www.buick-riviera.nl/pictures/73/7306blrr/7306001.jpg">



Erik

[Chris Lott]

Cool information Erik, thanks for sharing that with us. You'll have to pardon my ignorance, but what is LPG?:Do No:

[Bad Boattail]

Chris,

LPG (Liquefied Petroleum Gas) is a by-product of the refining process that turns crude oil into petrol.

Maybe it's better known as propane in the USA?

[Chris Lott]

There ya go; Propane. Thanks for the clarification:TU:.

[custom sky]

Erick, that is a wicked cool burn out. I think that I may have to check and see if any thing like that is available here. Might be a good project. Thanks again

[BlownNailhead]

Cool info Erik, LPG does make a good engine fuel. You can get back some of the lost power by increasing your compression ratio to take advantage of the higher octane rating of LPG. BUt of course that would mean taking your engine apart and new pistons. It looks like it is running just fine as it is.

Another advantage of LPG as you said is that the engine burns very clean. I had a friend that got a 350 Chevy from a LPG powered box van. That engine was spotless inside, and very little wear at all. This engine was a 150,000 mile engine as well.

[Bad Boattail]

BlownNailhead,

Compression is a cool 10.3:1 now
.030 overbore
bigger valves
GS cam
ported heads
<img src="http://pic7.picturetrail.com/VOL219/1017533/1899016/22628134.jpg">
<img src="http://pic7.picturetrail.com/VOL219/1017533/1899016/22627927.jpg">

For running on LPG you need a stronger spark, I have a HEI with a super-coil now on the engine.

Also the sparkplugs need to be upgraded to a higher heat-range


<img src="http://www.buick-riviera.nl/pictures/73/7306blrr/7306003.jpg">

Erik <--with a K!!!

[GSThunder]

Erik, I work at our municipal garage and we used to run dual fuel vehicles. I have a few questions for you if you don't mind.
We often had problems with carbon breaking loose in the cylinders on these dual fuelers making for a nice "knock,rattle and roll" if you know what I mean. The manufacturer of the system we used said they traced it to the fact that LPG was so clean burning it was "cleaning " the cylinders.The only way to repair was to remove the head off the offending cylinder and remove the carbon.
We had a few vehicles burn up due to underhood leaks. I have my suspicions that this was due to the fact that there were so many extra hoses added to the engine compartment.Have you experianced any leak problems.It is quit easy to locate LPG leaks as everything gets frosted with ice around the leak.
And I will concure with you about the mileage, our was always worse on LPG.We eventually got rid of all dual fuel systems as maintenance costs out weighed any fuel cost savings. I do wish I had saved one system so I could have "played" with it :Brow:
I'm glad your system seems to have these problems worked out.

[68lesabre]

Hi there EriK

As a fellow "Dutchman" and owner of a '68 lesabre that runs on LPG, I have to back you up on your LPG story.
TU:
I bought my lesabre in December 1998 and one of the first things I had done was to have a LPG installation installed. Since then I drove this car quite some kilometres. The first two years I owned it I drove it daily to my work and two years ago we even went on vacation to Austria and northern Italy with this car. I have never had any problems with neither the LPG-installation nor the engine itself.
It's "just" a 350 engine and fuel consumption is about 22 litres on 100 KM (approx. 10.5 miles a gallon)
Last year I went to Canada and bought a '68 lesabre convertible. I haven't driven it that much because it was September before I got the final papers (title) and by then we didn't have that much "convertible"-weather anymore. I want to drive it on petrol this summer and maybe put in a LPG-installation next year.
Erik; I live near Maastricht. Whenever you’re in the neighbourhood just let me know and maybe we can do some cruisin' around here.


:beer

[David Gramlow]

My oldest brother had a dual-fuel setup on his 68 GS400 back in the mid-70's when gas prices went thru the roof. Mileage suffered a bit, but propane was about 1/3 the cost of gas at the time. We also ran one of our tractors on LPG, and he also converted his 74 Chevy pickup to dual-fuel. Flip of a switch and you could run on gasoline, and the LPG system had a switch to change from liquid draw, to vapor draw from the trunk mounted tank. In the winter if temps got to about -20 F, the liquid had a tendency to freeze up in the lines, so you would run on vapor for a few minutes before you shut down the engine.

[Rivi69]

Hi Eric,

Love the burn out, I also have my Riviera running LPG, for the same reasons as you, same deal here in Australia. I tank only hold 55 Litres so you can imagine I dont get that far. I was trying to open your pictures as I'm so keen on your 118 litre tank, but for some reason I cant open them, could you send them to me directly, (are they Jpeg) ?:stmad:

[flynbuick]

Erik:

Goed morgen van de USA! Echt mooi auto! Mijn vrouw is een Nederlander.


Jim Lore