Why Propane ??

[dyeager535]

Well, the increase is 9HP, but at what cost to economy?

Ahh, thats right here:

Fuel consumption on Autogas is higher than petrol due Autogas having slightly less heat value per litre than petrol. Because current technology gas systems have very basic fuel management criterion compared to the advanced OEM computers, Autogas fuel consumption is increased approximately 27% over petrol operation. The GTi system utilises all the benefits obtained by the OEM engine management and results in a 10% - 15% improvement in fuel consumption compared to current Autogas technologies. This produces significant savings over the life of the vehicle.

So if I read that right, you lose about 15% of economy. You burn 15% more fuel (albeit a lot cleaner), and get less than a 15% boost in performance. More like 4% increase in torque.

Just don't see that passing a common sense test unless the fuel itself is more than 15% cheaper. (if you want to save money in the long run)

Time to go research what a purposely built propane fueled engine can do.

 

[jekbrown]

i don't think fuel economy is a sane reason to switch to propane... doesn't make much sense. All the $ in the propane kit could go towards gas and even if propane was cheaper, it'd be quite a while before you "broke even". Sorta like hybrid cars. Cost enough more that its like 8 years before you even break even on fuel costs. In any case, its run-at-any-angle capability, simplicity and clean-burning nature are the reasons to use it, not power or economy.

j

 

[dyeager535]

For fleet use it would seem to be quite effective. Oil/engine should last longer, in a big fleet I'm sure that adds up fairly quickly.

 

[CyberSniper]

That company I spoke of before...

Has like 15 F350s on gasoline and a dozen bobcat/work trucks. They get free propane from all the companies whose equipment they work on. Usually working on the equipment means emptying the tanks. Instead of recovering the propane they just put a giant stack on the tank and burn it off. This is a company that gets all products at company cost, has plenty of certified people to do maintenance/installation, and get free propane. And even they're not doing it.

I think their newest truck with propane on it is from like 1998.

Just like fuel injection, propane is not limited by fuel, but by oil as to what angles it can operate at. While a fuel pickup can suck air... if a propane system sucks liquid it's just as bad if not worse (frozen regulator).

 

[ntsqd]

One thing that hasn't been mentioned is that Propane is considered to be a 'dry' fuel. It has little to no lubricative properties. This usually shows up as burnt valves. Hard seats and good valves are a must with propane. I don't know the exact mechanism for propane burning the valves, but my former engine shop employer and friend learned this the hard way back in the 70's when propane conversions first became popular. Failed engines don't show signs of excessive heat (lean, poor IGN timing, etc.), but have failed valves anyway.
Being an alum head, the 22R should already have the hard seats.

 

[Blazr77400]

I just swapped my Turboed 6.2 diesel out for a 406 S.B. that runs on straight PROPANE and that was the best mod that I have done since I have owned the truck(next to the Mog axles). The propane is much cheaper then gas, $1.40 compared to $2.19 a gallon. Yeah, there is not as many fueling stations, but with the 80 gallon tank(usually gets 65 gallons in it) it has not been a problem.
I did get a cam spec'd for propane. I am also running dual carbs so I dont lose the power at higher rpm's. The compression is only 10:1 which 12:1 is just right for propane so mines on the low side. All in all, I am very happy with propane, and I would not hesitate to recommend it for somebody using it on their rig.

Propane is a fad just like quarter elliptical, turbochargers on 4wds, et cetera.

Propane is a fad for people who think inside the box.

It takes 1.4 gallons of propane to equal 1 gallon of gasoline. With propane costs so high these days it actually costs the same (or more) to run on propane.

I believe this is false as the truck I use to drive had the duel fuel setup on it. I usually only filled up one tank on the gas which was about 20 gallons. I always filled up the propane tank, which is the tank I am using now, so Around 65 gallons. When I used gas I could usually go 6-7 days and with the propane I could go around 3 weeks. And that was when gas was $1.75 and propane was $0.99. So you do the math.
(its around 9 gallons of gas to 10 gallons of propane)

You aren't going to get the performance out of propane either.

Unless you build the motor for it.

Fuel injection is pretty simple if you actually "get to know it". Emissions stuff can easily be eliminated if you send your ECM to somebody with the proper tools.

Propane is always going to be easier(and you dont have to get to know it) to work with then fuel injection, and even carbs. Fuel injection you still rely on electronics, and with F.I. and carbs you need a fuel pump. Propane doesnt need a fuel pump as its pressurized, and I have not touched my carbs since I have put them on. It starts right up every time. It doesnt seem to have to much of a propane smell, no more then the fork lifts at work. I also have no electronics on the fuel system, only one going to the motor(power to the distributor).

Propane pumps are basically glorified water pumps.

And where is the pump on a automotive propane system?

. if a propane system sucks liquid it's just as bad if not worse (frozen regulator).

I believe you actually suck fuel from the tank. Then the vaporizers turn the liquid propane into a gas form of propane.

Propane is rather dangerous. Nobody takes it seriously. Unlike gasoline, propane readily mixes with air to become explosive. It burns just as fast as gasoline when a line gets broken. If you have a leak, you might not notice it right away because the oil they put in the propane to make it stink isn't always that noticeable. Plus, propane is heavier than the atmosphere so unless there is a breeze to pull it off the ground it's going to sit as low as possible. Propane can also burn in two ways. First, there's the fire method. Second, there's the freezing method. Propane, when it squirts out, even as gas after a regulator, will burn your skin (freeze). This is especially true when you have a regulator that has enough flow to run an engine.

If you setup your propane kit CORRECTLY, you will not need to worry about any of this. Besides, what about static electricity at a gas pump, not much to worry about when filling propane.

All the $ in the propane kit could go towards gas and even if propane was cheaper, it'd be quite a while before you "broke even".

I spent a little over $650 for my dual carb straight propane kit. A mild 350 could live with a single carb very easily and the cost would be cut in half. So if you figure $325 for the swap, and propane costs $1.40 and gas costs a $2.19 and you get around 80% economy(will go lower for this example 80% instead of %90) If you drove 15,000 miles a year and ran gas at 10 mpg you would spend $3285 and no additional cost. With propane at 8 mpg it would be $2625 and with an additional $325 the total would be $2950. Not alot of savings, but you still see a difference.


Whether or not my reply made any sense or even mattered, I am very happy with propane, something I was skeptical about before I used it on a powerful motor, even though I used it on my daily driver.
Here is a good link about propane also Link.....

 

[mudslinger99]

What carbs are you running ? What tunnel ram ?

Are you set up to run both gas and propane ?

How would you rate the torque compared to gas with the same set up ?

Thanks for the info..


On a side note a 406 is a very good motor that produces alot of torque.. A buddy of mine had one in a 72 Blazer and that thing had so much power he could bust a U-joint any time he wanted with just a touch of the throttle.. In fact he carried a case of them in the truck

I looked at the pics of your truck and the build up and that thing looks like it would get the job done . I got a 84 that I'm working on slowly but shortly..

 

[kgblazerfive]

The carb that I'm running on mine is a stock Quadrajunk no mods the propane thing fits over the top and it just uses the carb for its throttle plates. I have yet to have any problems with it and the PO has had it on the truck since 82 and the truck is an 82. If I found another system I would swap the FI out of my Blazer in a heart beat, and I have like $700 in the FI already and still don't have a fuel pump. Just having the lack of moving or breaking parts of propane is a great advantage for me. The only problem that it has is in the winter it doesn't like to warm up but I have done nothing to try and fix that.

 

[darkshadow]

i wouldent recomend it if you live in the states and drive anywere.

My fishing buddy and his dad were driveing from BC to ontario thru the states.

he got about half way across when they ran out of fueling stations, then he used his last 40 bucks to make an adapter to hook a 20lbs bbq tank to the carb, bungeyed it to the shroud and ran out as he costed into the next station a state away!!!!

for a dd or streat/trail rig I wouldent to it.

but a trail only toy i would do it if the kit came up cheap

 

[Blazr77400]

On mine I am just running one of PROPANEGUY.COM dual carb system which uses 2 impco 425's, 2 model E vaporizers(regulator), and VVF 30 vacumm lock off. The intake is just an Edelbrock, low rise, dual quad intake from summit.

I would recommend a dual fuel for a daily driver.
I would recommend straight propane for an offroad rig only.

My brother is running a 400sb in his blazer which is about a 1000lbs lighter and runs on gas and I feel like I have more HP and TQ, but mine is a little more built then his. The only difference is mine has alum heads and a roller cam. He has 39's and I have 42's and can pull away from him in a race.

Once you go propane, You never complane
SP is wrong, I know.

 

[tom4]

It seems like everyone who is actually running propane loves it and would recommend it. On the other hand, those who arnt running it seem to hate it. So would someone who is actually running propane give me a little more info on it. What does it sound like? What is the best way to go to get the best power?........

 

[85mudblazin]

It seems like everyone who is actually running propane loves it and would recommend it. On the other hand, those who arnt running it seem to hate it. So would someone who is actually running propane give me a little more info on it. What does it sound like? What is the best way to go to get the best power?........

I love mine and will never go back to gas again.
As for what it sounds like, well it kind of sounds metally (if thats even a word). Doesnt really sounds much different.

For best power there are only 2 adjustments you can make so you just have to play with them to see what is best for your setup. With propane you are limited to a small block unless you want to get into a dual mixer setup which I think would just be a big headache.

Anything else you want to know, just ask away!!

 

[Citizen Rider]

Reading back on this post says a possibility of burn valves an whatnot?

Im thinking this maybe the next thing after 1ton. With rocks and trails, use with carbs often have trouble, and end up full throttle to get through the easiest of things(ask tom4). Although TBI gives the same charactoristics of propane, its alot more going on and to fail. Propane is so simple. Only problem is tank mounting IMO. And with some time spent on thinking, it can be used and still have plenty of room to carry cargo.

 

[berserker]

a few ?'s

what if you were to get a hole in the line and the thing went off like a flame thrower? or under the hood? gas is flamable but you can put it out very easily how do you put out a propane flame?
since the tank is under the truck what would happen if you landed on it? k-boom i know it takes alot to blow up a gas tank unless purposely done just a few ?'s

 

[mrk5]

That's why you don't mount the tank where it can get hit. Most guys mount them up in the bed area. If it was going in full-body K5, it would need to be an automotive vapor seal tank.

I don't know if all tanks come with them, but at least some have a safety vavle that will shut off flow if it becomes excessive - like from a cut line.

 

[74 chev]

what if you were to get a hole in the line and the thing went off like a flame thrower? or under the hood? gas is flamable but you can put it out very easily how do you put out a propane flame?
since the tank is under the truck what would happen if you landed on it? k-boom i know it takes alot to blow up a gas tank unless purposely done just a few ?'s

the lines used for propane are much different than a standard gas line a propane line is a braided steel hose it would be pretty hard to puncture one and you obviously run them out of harms way.

propane tanks are built very well i bet one could take a pretty good beating if it really came down to it my 80 gallon tank is 3/8 thick but ideally the point is to prevent putting it in a area suceptable to being hit.

BTW i also love my Propane system and wouldnt go back i have been running it for 4 years now and it has never gave me any real problems. im running dual fuel ri9ght now but im in the process of going to straight propane because i never use gas.

It pays off for me,runs clean,very simple,dont lose much power or MPG,to me its safer if anything than gas, And i have no problem finding fuel almost every hardware store and gas station has it now.

 

[mrk5]

my 80 gallon tank is 3/8 thick but ideally the point is to prevent putting it in a area suceptable to being hit.

Where'd you find an 80gal tank and how big is it (I mean the dimensions)?

I'm going to swap over to full-on propane and I'd like the operating RANGE of an 80gal tank.

 

[MattK]

Where'd you find an 80gal tank and how big is it (I mean the dimensions)?

I'm going to swap over to full-on propane and I'd like the operating RANGE of an 80gal tank.

ya, id kinda like to know where yall are finding these larger tanks. seems like a few of you are scoring them for next to nothing as well lol. not that i expect that, but knowing where to start looking would be mighty helpful.

 

[74 chev]

i got all my stuff for FREE LOL because my dad used to work at a Propane distributer. but the tank i have was just lying in the bon eyard there so i grabbed it and cleaned it up.
As for size its the width of my bed and as tall also sitting in front of the rear fender wells.

 

[AussieK5]

It seems like everyone who is actually running propane loves it and would recommend it. On the other hand, those who arnt running it seem to hate it. So would someone who is actually running propane give me a little more info on it. What does it sound like? What is the best way to go to get the best power?........

Posted this a few times now.....

From a previous post, might be applicable.....

Quote:
Ive run propane engines for years and recently built another engine up (my third for LPG). If you build it specifically for LPG you wont see any power loss over a petrol engine (92-96 octane).
They run and sound just like a petrol engine.
Cold starts are a breeze because of the homogenous nature of the fuel and the top end is only restricted by the size of the mixer, same as a under carbed pertol engine.
You will see power loss if you run a dual fuel setup because of the mixer having to be placed (usually) above the carb causing a constriction. I wont run a dual fuel set-up, I have in the past and recomend them to very few people.

Some standard setup points for a straight propane engine:

Compression: up to 10.5:1 (depends on the application and heads ie alloy heads vs iron and trail truck vs heavy hauler)

Timing: 10 deg at crank, Full adv by 2250 - 2500, If you tow max total adv should not exceed 30 deg.

Ignition: GM HEI considered a minimum standard, good leads and plugs also required.

Plugs: at range colder, maybe 2 depending on where and how you drive

Heat: Get rid of any heat risers etc that transfer heat to the fuel, LPG is gas and does not need it. This is a big thing, cool the intake charge and you will see a good change in power and economy.

Intake: Any single plane manifold with raised runners will give good service. It will idle like petrol factory manifold and run to what ever RPM you want. The raised runners help reduce intake charge temps.

Heads and Valves: Hardend seats and a good valve job, concentric seats, 45 deg face angles, no interference angle. Valve seats between 1/16 - 3/32 depending on the application

Rings and pistons: Whatever pistons you want for your application and if you want chrome rings break them in on petrol for a 1000 miles first otherwise it will take anywhere up to 60K to bed them on propane.

Cam: whatever suits you application really, you can get LPG specific cams here but they cost $$$ and the gains are almost negligible.

My K20 gives 11mpg on the highway with 4.56 and no OD. Unleaded is $1.30 AUD a litre at the moment and LPG is 42c....

HTH If you want any specific questions answered I'm more than happy to advise.

Jason

__________________

As someone said previously, those that have it love it and those that have never used it hate it.

If propane cost the same as ULP (ATM its less than half the price of ULP) than I would run ULP. For me its a cost issue.