Propane Conversion...and questions about it

[Redwolf]

Alright, well, I'm suffering a bit of car seperation anxiety. I'm in college (WOOOHOOO!!!! ), and parking is so expensive I decided to leave the Buick at home... But I've been racking my head for a while now about something.

 

When I left, gas prices had skyrocketed, to $2.50 a gallon (really pricey for us) from $2.20. Not a good thing. Not at all. I was thinking about alternative fuels one day, and was kind of comparing them all to see what would replace gasoline, if ever. I ruled out Hydrogen as a hippie fantasy, and bashed a few others (esp. hybrid cars, even though it's not technically alternative fuel), and ended up coming up with Propane, Natural Gas, and Alcohol (Methanol) as potential saviors from crazy gas prices. Just really bored at the time, you know.

 

Well, I started to think about this more and more, especially on Propane. Forklifts, if I remember right, have internal combustion engines, but they run off propane. Yet they are so clean they run inside closed areas no sweat. I started adding up some numbers, out of morbid curiosity, and found that per gallon, propane is cheaper than gas is. Don't remember by how much, it's been a while.

 

So, I started thinking the inevitable. What would it take to convert a car, specifically a Buick Regal running on an L36 engine, to propane? I know there are kits for this, but I don't know where to find them, or if they even make it for this kind of car. Would this be something DIYable, or do I need a mechanic to do the work (and pay a ton to afterwards)? (I know I'm messing with fuel lines, but as long as I tripple check everything and remove the gas first, I should be okay, right?) How much would this cost? I know there are some benefits, like how propane is more stable and runs at the equivalent of like 100-110 octane...but besides that...is it really worth it (keep in mind the engine is in perfect shape but is 130k old)? Even as a fun multiple-weekend project for next summer? What about those gas and propane kits, are they any better or would I really need it?

 

I'm not an enviromentalist by any means. I eat beef with pride, I've chopped down my fair share of trees with no remorse, and I'd gladly take a big-block 60s muscle car that spewed pollution for many drives if I had the cash (I hate SUVs, but for reasons other than the big engines...I like the big engines). It's just that gas is so expensive nowadays, and it doesn't look to be getting cheaper. There's no LNG places around here, and methanol isn't that readily avaliable. There are plenty of propane stations, so it looks like if I convert to anything, it'll be that.

 

This might be a question better left for Car Talk, but hey, you guys seem like you can help me out here.

[DaveFromColorado]

well, to convert to propane you're lookin' at a bit of work.

 

for starters, you'll have to rebuild your engine, and step it up to 13:1 compression ratio to get any efficency out of the propane, otherwise it will be so inefficent you'll use more fuel and get less power then with gasoline.

 

you'll have to ditch your old fuel tank, and you'll instead fab a mount so the tank is at least 6" above the lowest part of the car

 

you'll have to brace the tank/tanks to meet DOT codes in the case of an accident, you'll have to get the proper blow-down tubes in the case of overpressurization ... etc ... etc

 

and that's the easy stuff - but that's also the most expensive stuff.

 

next you'll have to find a good propane injection pump to supply the fuel to your fuel injectors - and you'll have to re-map your chip to handle the different fuel. it's a pain in the ass - and much easier on carb'd cars as remapping a carburetor means changing a couple jets.

 

Propane engines last LONGER, and run cleaner - meaning you won't get the contamination in your oil, if you change your oil at 3000 miles, it will still look new, even if your engine has over 100k on it (I've seen this before a few times)

 

the biggest downside to running propane in a car is if you don't allow a good honest 10 minute warmup before you start driving, durring those first 10 or so minutes you will literally use 3 to 4 times more fuel then you will when it is warm.

 

Road trips will suck, as you will have to plan arround LP stations - and those are hard to find.

 

just some thoughts for ya to think about. It's do-able without reworking the motor, but you'll lose some power and efficency.

 

--Dave.

[Robby1870]

If you wanna talk gas mileage and propane, use this rule of thumb: 5 gallons of gas = 6 gallons of propane. So, if propane isnt that much cheaper than gas, its not worth it. However, I do know a couple of guys running on propane right now and they have no problems.

[DaveFromColorado]

if you run the higher compression engine with the propane and get it tuned properly and warm it up every time you drive you can usually get it down to 5 gallons of gas = 5.1 gallons of propane"

 

on a side note.. I actually know where Terre Haute, IN is.. I bought a car on e-bay and it died there, so I sold it to a guy at the JD-Byrider for cheap (lost some money, but at least I made it home!)

 

--Dave.

[Redwolf]

I've been looking at a few sites about this, but nowhere do I see that the compression ratio needs to be tampered with. I know that gas and propane can be run in the same engine with a solenoid switch, which is what I'm looking to do.

[Jcrow]

The ignition timing is differant, and the air/fuel ratio is differant also. I know there are kits for carburated vehicles. I would imagine on a multi port engine you could just spray it in at one centralized spot (no fuel puddling in the manifold)

[Robby1870]

Sorry I couldnt make my post longer this morning but I had to give a presentation. So here is whatw I wanted to post this morning

 

My friend runs his truck (91 Chevy 2500 350) on propane or gasoline and all he does to go between the two is flip a switch in the cab. So, he runs the propane on the stock compression with no computer modifications. All he has is an evaporator and injections system, everything else is stock parts. The easiest way to run propane is to do this, just add on to a stock gasoline setup. Like Dave has said though, to get the most out of propane you have to build a motor for propane. If you can find propane for really cheap, then just slap on the stuff on your stock motor and go with it. With this setup you will notice a drop in hp.

[Robby1870]

on a side note.. I actually know where Terre Haute, IN is.. I bought a car on e-bay and it died there, so I sold it to a guy at the JD-Byrider for cheap (lost some money, but at least I made it home!)

 

--Dave.

 

You probably didnt miss much here. I just go to college here, one more year left.

[1990lumina]

I don't think running propane would be to difficult if you had the time and money to get everything set up properly.

 

I've noticed that though propane used to be less expensive around here (alot less expensive), it has significatly gone up in price lately (around here anyway).

 

I'm personally going to wait for hydrogen. I think the major thing holding car manufactures from running hyrdogen is the production process of hyrdogen. Right now, I believe that it costs way to much to remove the hydrogen from the water molecule. I believe electricity is used to unbond(it that a word?) the hyrdogen and oxygen, and the process just isn't cost effective.

 

Before the problem was that manufactures couldn't make hydrogen in a fuel cell safe (explode in a crash)...but I think they have fixed that prolbem for the most part.

It will happen one of these days. I just don't know how great it really will be.

[manitcor]

IMHO you would have an easier and chaper time getting an old diesel (like a VW rabbit, and old volvo or mercades) and converting it to run on part diesel part grease. (diesel to warm up, grese ot other bio fuels once warm)

[DiscoStudd]

IMHO you would have an easier and chaper time getting an old diesel (like a VW rabbit, and old volvo or mercades) and converting it to run on part diesel part grease. (diesel to warm up, grese ot other bio fuels once warm)

Just like they did in the "Off The Grid" episode of "30 Days." That would make the most sense, if you ask me. Biodiesel fuel is readily available, and if you convert the car to run on grease, you can easily obtain it from various restaurants (I'm sure they'd pay you to dispose of the crap!)

[DaveFromColorado]

I had an old 78 Rabbit Diesel, I loved that car, top speed of 76mph (unless commin' outta the mountians, then I got it up to 90 once before I fealt way too unsafe) we spent the $300ish to run on veggie-oil/fryer grease and once the car was warmed up, ya flip the switch - this is only good on long road trips because you still have to let the engine cool a bit with regular diesel, otherwise you'll kill your filter real quick. anyhow, I long lost about 3 mph from the top speed with the veggie-oil - it's a good alternative, and very cheap.

 

as for propane running on a stock setup, yes it will, very easily, but* the problem you'll have is you'll lose a bunch of MPG and HP because it's not built to handle the available anti-knock qualities of the propane and thus won't be making the most power it can.

 

--Dave.

[streetdreams]

my opinion on propane aside I think its a great money saver. I dont have any real knowledge on it but next time you get a chance call up some cab companies. Ask for info on where they get theyre repair work done or where they had propane installed into theyre cabs. it's alot cheaper than straight gas and obviously must save them alot of money if they choose to spend the money to have it installed.

[DaveFromColorado]

the biggest money-saver to the cab companies is in engine and transmission replacement - the engines last 2 to 3 times longer and because of the lower output power of the standard gas engine running on LP fuel the transmissions too will last longer.

 

I just called and asked "Suburban Cab" out here in the cities, and that was the response I got. They also hired their own fleet of guys who can fix/install the propane conversions - so it's all in-house with them.

 

--Dave.