Compressed Natural Gas (CNG) fuel Conversion For Light Trucks

A somewhat dated comparison of CNG & LNG is at

fdc/pdfs/2451.pdf , LNG is cold, so it boils off gradually and is more expensive. However, LNG stores (maybe) two and a half times more densely, so the vehicle gets greater range.

I'm concerned with CNG. Those are the engine conversions I want to do.

)~~( Nehmo )~~(

You might check

Maybe it would give you some ideas, at any rate.

Propane is a LOT more common conversion around here (Texas). Since propane liquifies under modest pressure (natural gas doesn't) you can get the same or greater driving range from a propane tank as from a gasoline tank. CNG vehicles are notoriously short range because of the limited mass of natural gas that can be carried in gaseous form. Austin had a fleet of CNG powered transit busses and light cars/trucks back in the late 90s, but they're all long gone. Converting the diesel engines in the busses to NG was much more complex than converting a gasoline engine to NG or propane, and the gasoline vehicles just didn't have the range to make them practical. Even with ready access to city-operated fuelling spots.

Adsorption technology offer significant reduction in pressures required to store CNG. This was a link in the message I got from the NGV global list,

To get around annoying excessive line wrap,

Below is the only supplier I've found for adsorption tanks in North America,

The largest tank there stores 130 cf at 275 psi, not much, the approximate equivalent of a gallon of gasoline. The tanks are approved by the US Dept of Transportation and Transport Canada.

Various sources claim that 500 psi using the adsorption technology will give the same storage as 3500 psi with standard CNG tanks.

Here in Brazil it costs, including professional installation, inspection and the required paperwork for the transit department, around 2K usd. The other big brand is Oyrsa (http://

The major brands are all from Argentina, they have been doing conversions for a long time. Fueling with propane is simpler, but not legal here.

My brother has a car that runs on CNG. It's a '98 GM Corsa.

-- Tiago

Here in Brazil it costs, including professional installation, inspection and the required paperwork for the transit department, around 2K usd. The other big brand is Oyrsa (http://

The major brands are all from Argentina, they have been doing conversions for a long time. Fueling with propane is simpler, but not legal here.

My brother has a car that runs on CNG. It's a '98 GM Corsa.

-- Tiago

I thought you COULD use propane in the newer multifuel cars??? I came into Rio a couple of years ago in a taxi that was capable of three different fuels.

What part of Brasil are you from? I lived there some years ago and still " tenho saudade pra o meu Brasil"..

Can you say anything about why it died out?

Propane is subsidized by govt, as it is the primary fuel for cooking. The new multifuel cars that runs on 100% pure ethanol to 100% pure gasoline and is also able to run on CNG. Actually only Fiat makes a car like this, called the Siena Tetrafuel, all the rest must be adapted by an independent converter.

Gasoline, ethanol and CNG.

I live in northeastern...

-- Tiago

I lived in Bahia...Never forgot how much I enjoyed the country.