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Discussion Starter #1
i have a 01 7.3. i was thinkin about puttin propane injection in it. I was wonderin what kinda cons that might have?
 

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Biggest con is having your engine block in pieces on the highway.

Propane used in VERY SMALL quantities can improve mileage slightly. However, propane is not as popular as it used to be because of so many people blowing up engines with it. If you want to use pane for power, have a spare block ready to drop in at a moment's notice.

There is an issue of using propane on a 99-03 7.3L - and that issue is split shot injection. Your 01 stock injectors fire a pilot shot of fuel before the main event, and that pilot shot will prematurely ignite the propane, causing a huge advance in injection timing. It causes a very early and rapid spike in cylinder pressures, and since it ignites too soon, it really doesn't have a huge effect on mileage.

Best bet IMO is to stay away from propane.
 

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Discussion Starter #3
ok. thanks for the advice. any advice on what to do to increase power without havin to get a chip for my truck? or is that kinda my only option
 

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ok. thanks for the advice. any advice on what to do to increase power without havin to get a chip for my truck? or is that kinda my only option
A chip is the best option. The only way to get more power is to add fuel.

Adding fuel any other way besides using a chip is either by way of adding drugs like propane, or by fooling sensors (the crude/cheap and not always best way of adding power).
 

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Discussion Starter #5
i got ya. i heaard thar ts and dp tuners are pretty good for 7.3. are there any other chips out their that are pretty good for a 7.3
 

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I've run DP-Tuner for years and really like it. Other good chips that also come highly recommended are Power Hungry Performance, Diesel Innovations, Swamps, Gearhead Automotive, and Total Diesel Performance.
 

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think you would be hard pressed to, find someone with a manufactured system that has sustained the kind of damage described, unless there was something done.
In fact, most people have run their system for years and use it everyday. As long as you don't have to use a ton of propane, you will save $$ and the modest power gains of around 60-80 rwhp is a bonus.

Yes, most people who think a little is good, more will be better, don't understand the idea behind propane fumigation in diesel engines. They throw everything but the kitchen sink at their engines, stacked boxes, injectors, nitrous, then try to make big power with propane. Radical tuning has caused its share of windowed blocks as well. You would get the idea from reading some of these posts that propane is the only bad thing you could do to your truck.

Most of the damage done is from those running acetylene regulators, and bbq tanks, or some other homemade setups, trying to save a few bucks. There is no regulation, metering or control to such a setup and as such, they use far too much propane, rampantly, and then have problems. You don't save much money when something goes wrong.
 

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think you would be hard pressed to, find someone with a manufactured system that has sustained the kind of damage described, unless there was something done.
Quite the opposite, actually. It happened a lot. In fact, there are fewer manufactured systems on the market today than there were 5 years ago. In addition, many vendors quit offering propane systems. Why? Because motors were popping left and right.

You don't hear as much about motors popping now because fewer and fewer people are running propane. 5 years ago if you attended any drag racing, sled pulling, or dyno event, there were plenty of trucks running propane. Today, you'll have a very very hard time finding a single truck still running propane. Most of those engines have already destroyed themselves.

How about those people using very small amounts of propane for mileage only? Well, quite a few of those engines have popped too. 5 years ago you would see diesels with propane tanks in the bed of the truck. Now, I can't remember the last time I saw one. Used to see a lot of people on vacations with their diesel trucks and camper trailers in tow - many of them with propane tanks in the back with feed lines running to the engine. Now, I can't find any of them anywhere.

Ask yourself what people are doing today. Nitrous and straight water injection are the popular choices, and what you'll see on a majority of trucks running any kind of "drugs" on their engines.

Propane is no longer popular or even recommended by most people and vendors. There's a reason why.

In fact, most people have run their system for years and use it everyday. As long as you don't have to use a ton of propane, you will save $$ and the modest power gains of around 60-80 rwhp is a bonus.
60-80 rwhp gain means you're running twice as much propane as what most consider "safe". Personally, I don't recommend any amount of propane. However, those that do generally recommend a max 40 rwhp gain - or less.

Yes, most people who think a little is good, more will be better, don't understand the idea behind propane fumigation in diesel engines. They throw everything but the kitchen sink at their engines, stacked boxes, injectors, nitrous, then try to make big power with propane. Radical tuning has caused its share of windowed blocks as well. You would get the idea from reading some of these posts that propane is the only bad thing you could do to your truck.
Can you blow up your engine with chips and programmers, injectors, etc? Yes. However, your chances of losing an engine running propane are significantly higher than any other single mod you can add on your truck. The reason why is there is nothing you can do to eliminate the cylinder pressure spike when running propane. You can try to control it, you can try to reduce it, but you can never get rid of it. Fuel in the cylinder is going to ignite, and propane is introduced at the same time as the air. It's going to burn, and you can't control when it decides to ignite.

Aftermarket injectors - can be precisely controlled as to when fuel is injected, and thus when the fuel ignites.
Chips/programmers - can control when fuel is injected, and thus when it ignites.
Nitrous - is NOT a fuel.
Water - is NOT a fuel.
Propane - is a fuel, cannot be controlled as to when it is injected, and thus cannot be controlled as to when it ignites. The ONLY thing you have control of is quantity.
 

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There are many manufacturer's still making and selling propane systems. They are appearing on large trucks and fleets, do some research and I think you will find the original manufacturers are still around and still offering their systems. Those that didn't work or did damage, have gone by the wayside as they should. They gave the technology a bad name, as did home made systems that would work as you suggest, uncontrollably.

There are many more options for power now than there was a few years back, and the vendors probably make a ton more $$ on a turbo and injectors than they do on a chip or propane system, so maybe they "push"other items. It does not equate to the death sentence you have handed down.

I would try to explain about exactly how propane fumigation is intended to work, but if are stuck on the notion that it ignites first, raises cylinder pressures, etc, etc, the talking points, we have all heard, then no equation or facts or figures , or chemical properties, would convince you otherwise. Propane can NOT ignite on it's own as long as it is below it's LEL (lower explosive limit), now as I said previously, with a rogue system with no control, you could get enough to the point of detonation, it still needs the diesel event to take place first.

Water/methanol systems are the same, no one knows just how much meth to inject or when. Same problem for folks when they add too much. Same as homemade propane systems. Blanket statements do not serve to answer the question.
 

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I would try to explain about exactly how propane fumigation is intended to work, but if are stuck on the notion that it ignites first, raises cylinder pressures, etc, etc, the talking points, we have all heard, then no equation or facts or figures , or chemical properties, would convince you otherwise. Propane can NOT ignite on it's own as long as it is below it's LEL (lower explosive limit), now as I said previously, with a rogue system with no control, you could get enough to the point of detonation, it still needs the diesel event to take place first.
Since you won't explain, I will. And by the way, you mis-spoke when you referred to "lower explosive limit". LEL and UEL refers to air/fuel ratios, and the absolute leanest and richest conditions in which a gas or liquid can ignite. By the way, propane has leaner UEL's and LEL's than gasoline. Meaning it can still ignite in leaner conditions than gasoline. Diesels often run leaner than gasoline engines, so much of the time we are still well within the LEL for propane. If you're going to convince me of something, please make sure you know what you are talking about first.

Here's the only thing you have going for you in this discussion is this - propane has a higher autoignition temperature than diesel. But that advantage disappears with pressure, as I'll explain further down.

Now, let's look at the properties of propane:
Propane has a lower BTU content than diesel. That's right, lower. So in order to get that "60-80hp" gain that you find "moderate", that's a LOT of propane. Way more propane than the amount of diesel needed to make an equivalent power gain. This also means it takes a proportionally larger amount of propane to substitute for diesel fuel when trying to use propane for mileage gains. So the cost benefits can suddenly disappear when propane fuel rises in price.

Propane has a lower flash point (but higher autoignition). What this means is that propane can burn and continue to burn at lower temperatures than diesel, but ignites without a spark at higher temperatures than diesel. Now, I mentioned that the only thing you had going for you in this discussion is that propane has a higher autoignition temperature than diesel. This is true. However, that autoignition temperature drops significantly (and much faster than diesel) when under pressure. The reason is that propane is in a gas state inside the combustion chamber, and gasses drop autoignition temperatures faster as pressure increases. Diesel is injected as fuel droplets - meaning its not in gas form, but rather still a liquid (and liquid doesn't compress). So now, you have a piston moving up, compressing the propane, and as it approaches TDC it reaches the pressure/temp point of autoignition. Here's the catch - if you are running larger amounts of propane for power gains, that autoignition point can be reached BEFORE the diesel is injected in certain cases.

Propane burns faster than diesel. Nearly as fast as gasoline. What this translates to in a diesel engine: a more uncontrolled and rapid explosion. If you were to graph cylinder pressures, you would see a faster rising, faster falling, and higher spiking CP curve when using propane. This is not optimal for diesel longevity, and puts more stress on head gaskets and rods. A more gradual rising and falling CP with a lower peak will produce lots of power at greater reliability. The purpleish looking spike is a general representation of what your CP curve would like running propane. The red is a graph of what CP's should be when running diesel fuel only.



Again, that's just a general graph I stole (I was too lazy to draw my own). In reality, that purple curve would be moved more to the left at an earlier point before TDC.

Spiking CP's is what kills engines. Any time propane is introduced, CP's spike. That spike can be somewhat controlled with the amount of propane used, but you can never eliminate that spike completely unless you cut off the propane supply.

Water/methanol systems are the same, no one knows just how much meth to inject or when. Same problem for folks when they add too much. Same as homemade propane systems. Blanket statements do not serve to answer the question.
FWIW, I said "straight water", and never mentioned water/methanol. But yes, the exact problems can arise with water/meth and using too much methanol.


Is propane all bad? Well in very very very small quantities - no. If you limit the propane to a very low level, you won't reach CP's high enough to do big damage over time. However, your HP gains will be at a bare minimum, as well as your mileage gains. If you do a cost/benefit analysis on such a small quantity of propane, the recovery costs are stretched out over a much much longer time period, and sometimes are never recovered if propane prices are too high.

Yes I looked into propane years ago for my truck. After doing this type of research and learning about the properties of propane vs. diesel, learning about the effects of cylinder pressure and damage it can do over time, and then looking at recovery costs of using lower amounts of propane, I decided that propane is not worth the expense of buying a kit and putting it on my truck, and not worth the risks. If anyone wants to put propane on their truck, then go for it. But I would always caution that you should learn as much about propane and your specific engine before throwing a kit in there. If this thread is at least somewhat educational and opens a few eyes for people, and those running propane take steps to ensure longevity and minimize CP spikes, then it has accomplished its purpose.
 

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So why the hard on for propane? If you've never even owned a system?
Because the diesel community in general has already figured all of this out a few years ago. Then you come on and recommend power levels of 60-80hp gains on propane, when that's already been proven to be a big no-no.

All anyone has to do is search the forums for propane users. You'll find some people have run their systems for years without problems, and nearly all of those are running about half the propane you suggested. Then you'll find threads where people have blown their engines due to propane. They might have had the system on for a few months, or it might have been on for a few years, but the end result has always been pointed back to propane causing either a rod to exit, or headgaskets to blow - both directly attributed to cylinder pressure spikes.
 

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There are many manufacturer's still making and selling propane systems. They are appearing on large trucks and fleets, do some research and I think you will find the original manufacturers are still around and still offering their systems. Those that didn't work or did damage, have gone by the wayside as they should. They gave the technology a bad name, as did home made systems that would work as you suggest, uncontrollably.

There are many more options for power now than there was a few years back, and the vendors probably make a ton more $$ on a turbo and injectors than they do on a chip or propane system, so maybe they "push"other items. It does not equate to the death sentence you have handed down.

I would try to explain about exactly how propane fumigation is intended to work, but if are stuck on the notion that it ignites first, raises cylinder pressures, etc, etc, the talking points, we have all heard, then no equation or facts or figures , or chemical properties, would convince you otherwise. Propane can NOT ignite on it's own as long as it is below it's LEL (lower explosive limit), now as I said previously, with a rogue system with no control, you could get enough to the point of detonation, it still needs the diesel event to take place first.

Water/methanol systems are the same, no one knows just how much meth to inject or when. Same problem for folks when they add too much. Same as homemade propane systems. Blanket statements do not serve to answer the question.

You would be hard pressed to find people more intune to there diesel motors then the guys on these websites. None of us hide from our experances, and problems over the years. Some of us know more then you want to believe...

How much cylinder pressure testing have you been involved in?

Powershotone, who are you? judging by your user name I would guess you work for, or own a propane injection company...


Since you won't explain, I will. And by the way, you mis-spoke when you referred to "lower explosive limit". LEL and UEL refers to air/fuel ratios, and the absolute leanest and richest conditions in which a gas or liquid can ignite. By the way, propane has leaner UEL's and LEL's than gasoline. Meaning it can still ignite in leaner conditions than gasoline. Diesels often run leaner than gasoline engines, so much of the time we are still well within the LEL for propane. If you're going to convince me of something, please make sure you know what you are talking about first.

Here's the only thing you have going for you in this discussion is this - propane has a higher autoignition temperature than diesel. But that advantage disappears with pressure, as I'll explain further down.

Now, let's look at the properties of propane:
Propane has a lower BTU content than diesel. That's right, lower. So in order to get that "60-80hp" gain that you find "moderate", that's a LOT of propane. Way more propane than the amount of diesel needed to make an equivalent power gain. This also means it takes a proportionally larger amount of propane to substitute for diesel fuel when trying to use propane for mileage gains. So the cost benefits can suddenly disappear when propane fuel rises in price.

Propane has a lower flash point (but higher autoignition). What this means is that propane can burn and continue to burn at lower temperatures than diesel, but ignites without a spark at higher temperatures than diesel. Now, I mentioned that the only thing you had going for you in this discussion is that propane has a higher autoignition temperature than diesel. This is true. However, that autoignition temperature drops significantly (and much faster than diesel) when under pressure. The reason is that propane is in a gas state inside the combustion chamber, and gasses drop autoignition temperatures faster as pressure increases. Diesel is injected as fuel droplets - meaning its not in gas form, but rather still a liquid (and liquid doesn't compress). So now, you have a piston moving up, compressing the propane, and as it approaches TDC it reaches the pressure/temp point of autoignition. Here's the catch - if you are running larger amounts of propane for power gains, that autoignition point can be reached BEFORE the diesel is injected in certain cases.

Propane burns faster than diesel. Nearly as fast as gasoline. What this translates to in a diesel engine: a more uncontrolled and rapid explosion. If you were to graph cylinder pressures, you would see a faster rising, faster falling, and higher spiking CP curve when using propane. This is not optimal for diesel longevity, and puts more stress on head gaskets and rods. A more gradual rising and falling CP with a lower peak will produce lots of power at greater reliability. The purpleish looking spike is a general representation of what your CP curve would like running propane. The red is a graph of what CP's should be when running diesel fuel only.



Again, that's just a general graph I stole (I was too lazy to draw my own). In reality, that purple curve would be moved more to the left at an earlier point before TDC.

Spiking CP's is what kills engines. Any time propane is introduced, CP's spike. That spike can be somewhat controlled with the amount of propane used, but you can never eliminate that spike completely unless you cut off the propane supply.


FWIW, I said "straight water", and never mentioned water/methanol. But yes, the exact problems can arise with water/meth and using too much methanol.


Is propane all bad? Well in very very very small quantities - no. If you limit the propane to a very low level, you won't reach CP's high enough to do big damage over time. However, your HP gains will be at a bare minimum, as well as your mileage gains. If you do a cost/benefit analysis on such a small quantity of propane, the recovery costs are stretched out over a much much longer time period, and sometimes are never recovered if propane prices are too high.

Yes I looked into propane years ago for my truck. After doing this type of research and learning about the properties of propane vs. diesel, learning about the effects of cylinder pressure and damage it can do over time, and then looking at recovery costs of using lower amounts of propane, I decided that propane is not worth the expense of buying a kit and putting it on my truck, and not worth the risks. If anyone wants to put propane on their truck, then go for it. But I would always caution that you should learn as much about propane and your specific engine before throwing a kit in there. If this thread is at least somewhat educational and opens a few eyes for people, and those running propane take steps to ensure longevity and minimize CP spikes, then it has accomplished its purpose.

leave it to Curtis to take the time to type what some of us just dont want to take the time to...

Thanks!

WOW!!!

So why the hard on for propane? If you've never even owned a system?

You win.....you know more than I.....
typical cop out...
 

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Just to add some "experience" to this thread-I ran a 60+ shot of propane through 2 different '99 7.3L diesels from '99-'05 and never broke anything in the engine. In fact, I would shoot a 100% max shot of propane into my truck on a weekly basis with no damage. I sold both of my trucks (one with 110K) without any engine damage whatsoever.

I did snap off 2 4R100 transmission input shafts :haha

I think propane lost its' appeal because of Nitrous and other easier gains of power. NOS gained popularity about 2 years after propane was popular. Also, chip tuners got much better at adding HP at that time. I remember "Superchips" had a 60HP chip and that was considered a lot in '99. Then within a few years, chips were adding 120, 150, then 200 HP.

Propane requires mounting a bulky tank, hoses and then there's always the "boom" factor if you're involved in an accident.

I removed mine because I had employees start driving my trucks.

I thought propane did a great job of providing lots of smooth adjustable torque. You'd be surprised how many medium & heavy trucks have propane assist on them.

Might not be able to post up any fancy graphs or scientific equations, but propane works and if used responsibly, will give years of reliable power boost. It's great for non-electronic diesels that can't be chipped, too.
 

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finally, someone to support a propane success story. some of you guys have "demonized" the notion, but I see no real convincing evidence of the negative properties of propane.
 
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