Fuel conversion on a car?

Feb 7, 2007
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Like LPG or natural gas?

There is also a bicarbonate conversion... know some people who got to reduce fuel consumption by up to 50% both on gasoline and diesel engines. Guaranteed savings of about 35%.
 

pedrochemical

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Aug 22, 2008
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Has anyone tried a conversion to gas?


Yes - there are 2 ways of doing it.

1 The Dominican way - slap a tank in the back and a few bits of kit here and there - total coast 700US$ and bob's your uncle! Start the car of a morning with the petrol tank, when it is warm you switch over to your propane.

2 The proper way. This way means messing around with either an extra carb or installing extra injectors and even some electronic doodahs (Thingamabobs) - but nobody apart from posh people do this. A couple of thousand buck should do it if you go this route.

Depending on how much you drive you will make your money back in a year or two.
People always myther on about how having a propane tank in the boot is dangerous - but for me having a petrol tank strapped underneath the car is just as dangerous.
 

Anastacio

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Feb 22, 2010
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Oh, I'm not bothered about all the bells and whistles, I'm more interested in how much more economical I can expect it to be and if there are any downsides other than I expect loss of power ( not really an issue in a car that will only do 90kliks at best) and unexpected rapid boost should someone hit me up the arse, lol.
 

beeza

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Nov 2, 2006
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The calorific value of LPG is about 20% lower than that of petrol. If you add that to the very inefficient method of installations that I have seen here, your mpg whilst running on LPG could be almost a half of what you get running on petrol.

Okay, so LPG costs 80 pesos a gallon vs 154 pesos for regular. Unless you are running a giant 5 litre V8, don't bother with a crappy conversion. I've seen a Merc ML V8 engine with an exploded plenum chamber and various other cars with disintegrated air boxes from bad gas metering.

If you want LPG, go for a proper sequenced injected Italian system like Tartarini or Landirenzo. I doubt there are any installers in this country, but I could be wrong.

If you want better fuel economy why don't you look at removing your catalytic converter? The chances are that the bad fuel has probably knackered it anyway. Unless you are worried about polluting the atmosphere, there is no benefit of having one on a car here. Get a garage to remove it and replace it with a piece of regular tube. If you know the right mechanic, he might even do it for free because he can recycle the cat for the precious metals that are inside it.

A de-catted car can return at least a 10 to 15% increase in performance and fuel economy. Couple that with a decent air filter, like a K&N, the savings could be even higher.
 

Anastacio

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Feb 22, 2010
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Of all things I have found a mx5 harvard in my possession. Crazy and rare here! Imu.
Things are pretty good but I'm crap at this side of things, I'm a paint and body guy and so lost. My thoughts are the car needs to be reregistered, I might as well reregister it with prop conversion for insurance purposes, but how doses that work, I plan on doing it or at least getting involved in it with someone with knowledge. My adoptive father does but he does the taxi conversions and I'm never completely confident with anything like that, I'd rather do it properly myself, with someone.
Opinions please?
 

cobraboy

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Jul 24, 2004
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There is much written here about propane conversions. I had a Romano professional conversion done on my '02 X-Terra and found the cost per mile averaged US$0.13 less than gasoline. I got 70% of the mileage on propane, but the cost of propane averaged around 45% of the cost of gasoline, so the cost per mile was less.

I never noticed a great difference in performance unless going up a very steep grade loaded with people. And them it wasn't a huge difference.

Important: your vehicle, especially if it's fuel injected, needs to run occasionally on gasoline and you need to keep fuel system cleaner in the gasoline to keep the gasoline system running properly. I didn't and found it ran funky on gasoline after a while until I discovered a simple fuel pressure regulator/return had failed, something difficult...and unusual...to diagnose, but simple to fix. Runs terrific now.

I'm selling the X-Terra and removed the system (19g tank, electronics, automatic switch, mixer/heater, etc.). If anyone wants to convert their vehicle to propane, I'll sell the system and have my mechanic install it for RD$20,000, a bargain.
 

Bryanell

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Aug 9, 2005
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If you want LPG, go for a proper sequenced injected Italian system like Tartarini or Landirenzo. I doubt there are any installers in this country, but I could be wrong.

I have a Tartarini fully integrated and digitized LPG system on my 1999 Isuzu Trooper 3.2 liter V6 DOHC.
The importers are LARA Gas S.A., Calle Respaldo 18 No.8, near the corner with Pepillo Salcedo, Ensanche La Fe, in Santo Domingo telephone 809 549 4839. (Last known address)

It was installed by the previous owner and like I said is fully integrated.The filler valve is positioned in the hatch next to the gasoline filler and the 25 gallon tank in an upholstered box, is in the cargo space behind the rear seats. It takes up most of the cargo space (which sucks) and the two jump seats had to be removed, but since I rarely have more than two passengers, not a great problem. There is a little 1.5x2.5cm pad fitted in one of the switch blanks on the dash with a LED display which shows if you are running on gas or gasoline with 4 LEDs displaying the amount of gas in the tank and an audible alarm when you get below a quarter full. There is a push button on this pad for manually switching between fuel systems.

The engine starts on gasoline and automatically switches to gas after a few seconds.
I guess there is some power/performance loss with LPG but I'm not a speed freak any more and for "normal" driving I don't find much difference between running on gas and running on gasoline, but I do make sure to have the maintenance done on time otherwise it can eventually muck up injectors and so on.

Nowadays with LPG half the price of premium gasoline and with the expected lower miles per gallon on gas, the saving today wouldn't warrant the cost of purchasing and installing that system, which, as was noted by another poster here, is between US$1,500 and 2,000. Also filling up with LPG is a bind because there are relatively few LPG stations, their pumps are slow and with so many folk running on LPG crowding the stations it can take half an hour sometimes to fill the tank. I only do it these days when I have to fill the kitchen gas cylinder and the whole round trip to my nearest LPG station on the Malecon near Metaldom takes an hour or so.

If your vehicle has a cat converter an easier way of economizing would be to take out the converter.
 

cobraboy

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The injector system for the Xterra was priced at roughly US$2700 2.5 years ago and the projected payback was very long, nearly 2 years. The payback of the simple system was a little over 6 months.

Even at the current fuel prices propane still costs RD$3.50 less per mile than gasoline in my vehicle, which is still US$ 9.5 cents per mile. The payback for the simple system is still under 8 months.

I've never had a problem finding a propane station. I just avoid them Friday afternoon before a price increase.
 
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Criss Colon

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MY FORD van rUNS On Propane.

I love it! Cheaper! Only costs about 15,000 in Santiago,about 3,500 more in SD. Includes tank and instalation. I start only on propane,no problen.
cccccccccccccccccccccccccccccccccccccccccccccccccc
 

DipreSantana

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Got an Xterra set up to take LPG, it starts on gas, and after about 3 minutes, switches to LPG, I've noticed though, that while on LPG, I have no torque, makes it much easier to stall.
 

bachata

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Aug 18, 2007
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I used LPG to operate my car for many years in DR driving a taxi for local customers but in the mean time I started making Dollars driving for tourist I got this stinky cylinder out of my trunk...
You guys making a living about American Dollars please leave that explosive and stinky devise for the poor taxi and carros publicos drivers who are struggling.

JJ
 

cobraboy

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Does he want to buy a bridge???????CCCCCCCCCCCCCCCCCCCCccccccccccc
It's one of the complex injector systems where holes have to be drilled into the intake runners and LPG injectors are installed.

Those are the better systems, but very pricy. The payback is much longer.

I have a good "regular" Romano system with round 19gal tank (goes where the spare tire is mounted under the vehicle), all new diaphragms, and fuel gauge/auto switch for sale for RD$19,000 installed.
 

bachata

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This is the best gasoline / LPG converter... After four years using one of theses American converter I pulled the gas tank from the bottom of my 1985 Honda Accord and through it away to make the car lighter.
IMPCO Parts - Impco 125 Carburetor for NG, LPG, Digester Gas
My car was running on LPG only I installed a LPG carburetor on the mounting bracket of the original gasoline carburetor (intake manifold).
If you install one of theses you won't have all the issues and the expensive maintenance you will have if installing one of those that come with the water and LPG diaphragms built off rubber as they get inflexible after two or three month.

JJ
 

cobraboy

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Jul 24, 2004
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This is the best gasoline / LPG converter... After four years using one of theses American converter I pulled the gas tank from the bottom of my 1985 Honda Accord and through it away to make the car lighter.
IMPCO Parts - Impco 125 Carburetor for NG, LPG, Digester Gas
My car was running on LPG only I installed a LPG carburetor on the mounting bracket of the original gasoline carburetor (intake manifold).
If you install one of theses you won't have all the issues and the expensive maintenance you will have if installing one of those that come with the water and LPG diaphragms built off rubber as they get inflexible after two or three month.

JJ
Doesn't work for EFI...
 
Feb 7, 2007
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OK, my comparison, Chrysler 2.4l, 6V., 4 cyl.
(intercity travel, with some city-transit) e.g. Higuey to La Capital, etc.
Both tanks are 16 gallons

LPG: 275 miles, cost per mile: 4.82 pesos
Gasoline premium: 360 miles, cost per mile: 7.38 pesos

I had an LPG burner (hornilla) changed a year ago, from "criolla" to "italiana" for a cost of 1000 pesos and my mileage on LPG went up 40 miles.

Make sure
- change air filter at least every 12 months
- change spark plugs at least every 8 months (you should not get platinum tipped ones)* get NGK
- clean LPG converter every 6 months

My incity consumption on LPG is only 40-45% of intercity, have not measured on gasoline (for that my gasoline tank would need to get full, which it didn't get for 3 years). I don't do much incity travel in my car, I used scooter better in Higuey, faster, cheaper, easier parking, and can get in front of everybody on traffic lights, and gets me 70 miles with 200 pesos.

* NGK spark plugs are designed for LPG, as I have been reading on Internet. Some time ago I got these without even knowing they were best designed for LPG and I have seen improved performance.
 
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cobraboy

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I'd suggest that everyone that has a gas conversion on their vehicle to do a comparison.

On a plymouth Minivan, I got the following results

20 gl. lpg gives me 140 miles, or 7 miles to the gal.

20 gl. of gasoline give me 315 miles, or 15.7 miles to the gallon.

Guess what? Gasoline is cheaper.
The reason folks convert is to reduce costs.

On my Xterra I am always doing calculations that take into account the varying cost of fuel. But every calculation points to the fact that it costs from RD$3.50 to RD$9.50 (when LPG was subsidized and gasoline was over RD$200) per mile ~less~ to operate in on LPG vs. gasoline in all conditions.

FWIW, you may want to have your LPG adjusted (it can be done.) If you're getting 15.7mpg on gasoline, you ought to be getting around 10mpg on propane...