LP gas vs gasoline... anyone using LP on their chevy?

[gildardo01]

is it worth it to convert an engine to run lp gas instead of gasoline.... i have a chevy stepside with a new 350 in it and its running on gasoline but i also have a nissan pick up running on propane and it runs great... i bought the nissan with the propane system already in it and it doesn´t even have a gas tank, it runs nothing but propane... where i live propane is about half the cost of gasoline.... should i leave it the way it is or should i convert it....  if i make the chevy run on LP its only going to cost me about 400-500 dollars...  what do you all think?

[choptop]

I ran propane in my 83 GMC crewcab dually. I had a 454 with a 4 speed, and had run propane since it was fairly new. I got 10 mpg on propane and close to the same on gas. It was odd tho, it ran awesome on propane, but gas was a different story. Even a new carb didnt change the way it ran on gas. The only hassle I had in Texas with it was I had to buy a permit to run propane, that was based off of how many miles I ran it, plus tank inspections..in the long run, it just wasnt worth it to me. Only a few stations local would fill it, out of town trips usually ended in running on gas only, and propane at the time was not alot different in price versus gas.. I ran it mainly because the truck just ran better on it.

[9511234]

I worked for the company that has one of the largest truck fleets on the road today with bi-phase LP technologies.

Benefits of LP is that it is clean... but there are two sides of that coin- it is dryer than a wet fuel.

I never had a problem with the LP system itself, but when we were stopping and starting the truck all day the engine would get hot and then the liquid in the pipes would seem to gas out, so it sometimes would take a bit to start back up if you didn't hit the pump up procedure just right.

I've heard that LP burns hotter than regular fuel as well - so that just adds to wear and tear.

Add the cost of inspections, finding a place to fill up, and wild seasonal price fluctuations, and I think any benefit is far outweighed by the cost in time and money.  It may be cheaper to run in the summer, but in the winter prices jump dramatically. 

If you ever run out of fuel on the side of the road - your only hope is either a tow, or having one of the lp delivery trucks run out and then be willing to hook up to your truck.  They don't work nights and weekends either.

If it's in the truck already, like your nissan, i would keep it in the truck.  But i wouldn't add it after the fact.

[gildardo01]

were i live we dont have either inspections, and finding a place to fill up is no problem. price isn´t fluctuating due to weather... you might be asking where is this place... well i currently live in mexico... so yeah... thats why there are all the benefits..
something i have read about running LP is that if you go too lean on the mixture, the valve guides tend to wear faster...
will running propane prevent carbon build up on the pistons? and what about the sludge in the engine will it prevent that too?
something that i think is a plus about running propane is that it might be more ¨pure¨  I can´t think of a better word... you know like gasoline here also contains ethanol and you really dont know what your getting and with propane i dont think they can add anything to make it cheaper for them can they?.. something else about gasoline here is that for some reason it smells different than over there in the states... it smells stronger, horrible smell... and sometimes regular gas might be bright red other times its a lighter pink... premium is always yellow kinda looks like the color of diesel not a lot of difference in premium fuel smells different sometimes though....

[9511234]

I know they add dyes to diesel so that for tax purposes one can't use farm diesel in a road car.
I don't know about other fuel types tho.
I think it would help with engine sludge- but it depends on oil changes and environmental factors.

Like I said- it is purer... but the downside with the purity is this:

It will run hotter.
I think MPG suffers very slightly, if any, almost positive your HP will suffer.
When you are not spraying a wet fuel, but instead a gassy mixture it doesn't cool the valves the same way fuel would- and that follows with the way it burns.

If you know how to dial in mixture- you should be set, if you run too lean on gas the same thing will happen- it will run hot and burn a valve.  You should be able to pull a spark plug and check if it is running too hot pretty easy tho- because it will have a white char on the end of the plug.

[werewolfx13]

Propane doesn't actually burn hotter, much like high octane gasoline, it actually burns "cooler", rather, has a HIGHER flash point. However, valve burn is a problem in the extended long run, shorter if you run lean, because, as said before, its not in liquid form once it enters the intake manifold, its completely vaporized, and doesn't quench the valves. This can be managed, but figure on more frequent head rebuilds if you run it hard. My long term plan for my '83 is to run it on propane exclusively with a high compression 383 stroker. I'm going to be researching additional lubrication/cooling options for the engine before the build, and I'm expecting comparable mileage on LP that I would get from a gasoline engine built for use on higher octane pump gas, and considerable kick in the pants. Where I buy propane, my price is fixed year round. I sell it at my store by the pound, and my discounted retail price after tax will be about $2.60/gallon.

[gildardo01]

i understand HP will suffer but only if it has low compression... and mpg evens out compared to the price difference between gas and propane... its just like alcohol, you need an engine that would take advantage of the high octane to make it as efficient as possible... i was thinking about later on adding a weiand 177 supercharger kit and adding a good amount of boost to take advantage of the octane in propane if i wanted to switch back to gasoline i could just change the pulleys...  think this would work? im not looking for a race engine... just a respectable amount of horses... ya know...

[gildardo01]

Propane doesn't actually burn hotter, much like high octane gasoline, it actually burns "cooler", rather, has a HIGHER flash point. However, valve burn is a problem in the extended long run, shorter if you run lean, because, as said before, its not in liquid form once it enters the intake manifold, its completely vaporized, and doesn't quench the valves. This can be managed, but figure on more frequent head rebuilds if you run it hard. My long term plan for my '83 is to run it on propane exclusively with a high compression 383 stroker. I'm going to be researching additional lubrication/cooling options for the engine before the build, and I'm expecting comparable mileage on LP that I would get from a gasoline engine built for use on higher octane pump gas, and considerable kick in the pants. Where I buy propane, my price is fixed year round. I sell it at my store by the pound, and my discounted retail price after tax will be about $2.60/gallon.

sounds like a very interesting build the 383 will be... i´ll be looking forward to reading about it if you post it on this website... and 2.60 a gallon compared to... whats the price of gasoline where you live? 2.60 sounds like a good price... it should be cheaper thought since propane is actually just a byproduct... but whats cheap now a days huh....

[werewolfx13]

I stopped paying attention to the exact amount on gas prices 3 years ago, and pay as little attention to the total price as I can. I think its around $3.8x. Our supplier (Ferrellgas) bills our store about $1.60/gallon, and they lock that price unless there is a MAJOR upswing in their cost. In two years they've only changed the price once, and that was from 1.83 to 1.60. If I had $4000 in my back pocket I could buy a certified filling setup minus the scale for weight filled tanks with a 300 gallon bulk tank and get a better price, but regulations on bulk fuel dispensers is pretty hefty, even on private property for private use. One like we use @ work runs $9000 for the rapid delivery pump, motor fuel meter and hose, OPD compliant hose for weighted tanks, the 3 common adapters, 500 gallon tank, enclosure for the pump, scale, meter, etc, and 1000lb capacity scale.