Thread: Custom gas injection??

Originally Posted by Dougal

The most common mix of nitrogen, oxygen, CO2 etc is known as "air", it's transport properties are very well known and understood..

well known but not understood, besides during and after combustion it not AIR now is it.

Originally Posted by Dougal

You have not explained at all why or how LPG won't increase EGT's.

.

for the same reason Hydrogen is added to diesel fuel
and I explained what EGT can be some of it is not applicable to NA. But then we have had this discussion before so I know you don’t have a good grip on this topic

Originally Posted by Dougal

The "unburnt fuel" argument is bollocks and mostly spread by sellers of lpg systems. With a good A/F ratio you are running clean and burning all the diesel regardless of power output.
You want another 25% power while running clean on diesel, it's easy..

but we are not talking about running good A/F ratios we are talking or more to the point you were talking about increased performance from a NA diesel by turning the screws, and as you would know that would instantly have an effect on your A/F ratio,

Originally Posted by Dougal

Please tell me you don't believe the claim of 25% unburnt fuel in a stock motor..

no, but you posted turning the screws so we are not comparing to a stock motor running clean AF ratios

Originally Posted by Dougal

That would make a cloud so black your rear view mirror will be useless. Your claim of 40% is truely amazing.

I have run quite a few at silly over fueling rates I did try to explain how this works but obviously you cant get to grips with this.
what i didn’t explain was these were racing motors not street. it was also quite damaging to the liners due to washing. but then these motors were not expected to last for a million or more Ks

Originally Posted by clean32

well known but not understood, besides during and after combustion it not AIR now is it.

for the same reason Hydrogen is added to diesel fuel
and I explained what EGT can be some of it is not applicable to NA. But then we have had this discussion before so I know you don’t have a good grip on this topic

but we are not talking about running good A/F ratios we are talking or more to the point you were talking about increased performance from a NA diesel by turning the screws, and as you would know that would instantly have an effect on your A/F ratio,

no, but you posted turning the screws so we are not comparing to a stock motor running clean AF ratios

I have run quite a few at silly over fueling rates I did try to explain how this works but obviously you cant get to grips with this.
what i didn’t explain was these were racing motors not street. it was also quite damaging to the liners due to washing. but then these motors were not expected to last for a million or more Ks

I don't believe you're a good source of information on this topic.

Air and exhaust transport properties are very well understood.
Hydrogen is not added to diesel fuel. Diesel is a hydrocarbon.
I did not say you could increase power on a NA 20% by turning screws. I said any such increase would result in dangerous EGT's. I stand by that comment.
A 25% increase in a turbo motor is not that difficult, especially on these motors.
Any increase in fuelling results in higher EGT's (unless it is matched by an increase in air density). I would like to hear any reason you have why you think this does not apply to an LPG fumigation system. Especially since LPG displaces some of our much needed air with more fuel.

We are talking about AF ratios, because they determine when you're going to start making smoke. Stoich on a diesel isn't far off stoich on a petrol, but the smoke limit on a diesel is about 18:1 if your injectors are working well. Production diesels run significantly leaner, hence the ease in obtaining a 25% power increase with the result of higher EGT's.

You should be very careful about quoting "marketing" material. It is quite common for it to be not only incorrect, but absolute fantasy.

Originally Posted by Dougal

I don't believe you're a good source of information on this topic. .

Well you can read and believe what you want, but I would advise you to read a weeee bit more, it would be good for you i believe.

Originally Posted by Dougal

Air and exhaust transport properties are very well understood..

I think you originally said "Known" I agree, I don’t believe that it is well understood. Knowing Corse and effect either by observation, experimentation or education is knowing is is however not understanding.

Originally Posted by Dougal

Hydrogen is not added to diesel fuel. Diesel is a hydrocarbon...

We have been over this topic before. Even one person posed a link to a report and stated that i was incorrect, how ever the report on reading stated that hydrogen is added.
fuel, hydrocarbon= hydrogen and carbon being the common elements. There is only ONE element on the periodic Table that " burns" and that is hydrogen. all other elements need hydrogen to be present to form a reaction. ( take that in context of this conversation)

Originally Posted by Dougal

I did not say you could increase power on a NA 20% by turning screws. I said any such increase would result in dangerous EGT's. I stand by that comment.
A 25% increase in a turbo motor is not that difficult, especially on these motors....

Ok i miss read your post, and i agree that with a turbo that a 20% gain is quite easy to do with the motor in question. But please do not confuse EGT with CCT, as I attempted to explain there are a lot of other influences that need to be taken into account with EGT that are not present with CCT. it is even possible with large over fuelling to have a lower CCT and a higher EGT.

Originally Posted by Dougal

Any increase in fuelling results in higher EGT's .....

incorrect

Originally Posted by Dougal

(unless it is matched by an increase in air density).
.....

increase in Mass not just density- correct

Originally Posted by Dougal

(
I would like to hear any reason you have why you think this does not apply to an LPG fumigation system. Especially since LPG displaces some of our much needed air with more fuel.....

" displaces much needed air" misleading statement. as you know the AR ratios have a surplus of air as well as the volume of LPG is miniscule. so that’s a non argument.
add to that LPG molecule is quite Large compared to oxygen witch is an element, nitrogen is also an element and CO2 molecule is very small in comparison so to some extent it is likening to filling a bucket with sand saying its full but then adding water.

You can add the water first, sand will displace some water but not all and not by an equivalent volume

but back to your question C3H8 and C3H10 = LPG, cetane C16H34 is the good bit in diesel. unfortunately diesel comes with a hell of a lot of other impurities but i will not cover that now as its is a big topic.
If you look at the ratio of carbon elements to hydrogen elements, this ratio improves with addition of LPG and more especially butane ( C3H10)
in simple terms the reaction is just taking a bunch of carbon attached to hydrogen, adding some oxygen and changing it all to H2O CO2 ideally.
the problem is that we also produce in an incomplete burn nitrogen/ oxygen molecules. And incomplete burn may be because of lack of time ( high rpm) CO, to much CCT ( nitrogen oxides) simple so far. Now by adding extra hydrogen molecules umm how to explain this? When a burn starts the molecules break down race around trying to re organise themselves. The more hydrogen molecules there are the less racing around they have to do, the less heat is produced in the reaction but a more complete reaction is completed ( given the same amount of time)
then you have to look at the new molecules that have been formed and how they behave at temperature. water for example is much harder to compress in its steam state than CO2 is, so as a more complete burn will produce more H2O and less CO2 IE at 200deg steam needs ( if i remember correctly) 300psi compared to CO2 which needs only 140psi. ( i haven’t checked so don’t quote the last numbers.

Originally Posted by Dougal

(
We are talking about AF ratios, because they determine when you're going to start making smoke. Stoich on a diesel isn't far off stoich on a petrol, but the smoke limit on a diesel is about 18:1 if your injectors are working well. Production diesels run significantly leaner, hence the ease in obtaining a 25% power increase with the result of higher EGT's..

correct and an increase in CCT, NO CO and all the othere bad stuff

Originally Posted by Dougal

(
You should be very careful about quoting "marketing" material. It is quite common for it to be not only incorrect, but absolute fantasy.

Originally Posted by long stroke

Hi all
We met another isuzu county owner today
We got talking to him for a while and he showed us his custom gas injection system he made up.
All it is, is a BBQ gas bottle that sits in the cab with a hose leading into the intake manifold and when he wants a little bit more power he turns the bottle on!
Mainly only needs it for hills and over taking
He claims it added about a 1/3 more power to it
My question is has anyone on here done it?
And would it shorten the life of the motor or anything?

Thanks in advance TIM.

Let me paint a picture Mr Elcheapo Gasconversion hits the base of a hill engages gas bottle via tap gains his 30% power increase.
At the crest he hits a Commodore head on the ensuing explosion and large crater in the ground are the result of his gas bottle that
continued to discharge gas while he was unconscious.
I trust no one here is this STUPID

Originally Posted by clean32

fuel, hydrocarbon= hydrogen and carbon being the common elements. There is only ONE element on the periodic Table that " burns" and that is hydrogen. all other elements need hydrogen to be present to form a reaction. ( take that in context of this conversation)

Far from the truth. Burning is chemical oxidation which happens to most of the species on the periodic table.
If you have a better definition, now would be the time to post it.

Originally Posted by clean32

Ok i miss read your post, and i agree that with a turbo that a 20% gain is quite easy to do with the motor in question. But please do not confuse EGT with CCT, as I attempted to explain there are a lot of other influences that need to be taken into account with EGT that are not present with CCT. it is even possible with large over fuelling to have a lower CCT and a higher EGT.

You need to explain this a lot more. The only way you can get a higher EGT with a lower cylinder temp is from a very slow burning fuel. LPG is not a slow burning fuel when compared to diesel.

Originally Posted by clean32

increase in Mass not just density- correct

Durr

Originally Posted by clean32

" displaces much needed air" misleading statement. as you know the AR ratios have a surplus of air as well as the volume of LPG is miniscule. so that’s a non argument.
add to that LPG molecule is quite Large compared to oxygen witch is an element, nitrogen is also an element and CO2 molecule is very small in comparison so to some extent it is likening to filling a bucket with sand saying its full but then adding water.

The stoich ratio for LPG is approx 20:1. It displaces 5% of it's air with a fuel which has a comparatively low energy density.

No-one is injecting sand (granular solids), only gases and vapourised liquids.

Originally Posted by clean32

but back to your question C3H8 and C3H10 = LPG, cetane C16H34 is the good bit in diesel. unfortunately diesel comes with a hell of a lot of other impurities but i will not cover that now as its is a big topic.

The average composition of diesel is around C7H14, as you can tell from the ratio of C:H this is not a typical x2+2 hydrocarbon chain, it's a mix and that's the average.

Cetane is a rating system.

Originally Posted by clean32

If you look at the ratio of carbon elements to hydrogen elements, this ratio improves with addition of LPG and more especially butane ( C3H10)
in simple terms the reaction is just taking a bunch of carbon attached to hydrogen, adding some oxygen and changing it all to H2O CO2 ideally.
the problem is that we also produce in an incomplete burn nitrogen/ oxygen molecules. And incomplete burn may be because of lack of time ( high rpm) CO, to much CCT ( nitrogen oxides) simple so far. Now by adding extra hydrogen molecules umm how to explain this? When a burn starts the molecules break down race around trying to re organise themselves. The more hydrogen molecules there are the less racing around they have to do, the less heat is produced in the reaction but a more complete reaction is completed ( given the same amount of time)
then you have to look at the new molecules that have been formed and how they behave at temperature. water for example is much harder to compress in its steam state than CO2 is, so as a more complete burn will produce more H2O and less CO2 IE at 200deg steam needs ( if i remember correctly) 300psi compared to CO2 which needs only 140psi. ( i haven’t checked so don’t quote the last numbers.

I have no idea where you're going with this or why.

Compre the autoignition point of propane with the compression temperatures of diesel. When you've done this tell me why running on preignition is a desirable outcome.

Originally Posted by Dougal

Far from the truth. Burning is chemical oxidation which happens to most of the species on the periodic table.
If you have a better definition, now would be the time to post it..

Wrong there is only one element that burns and there are no chemical or species on the periodic table only elements. Oxidation is a different reaction, like Rust, ferrous to ferrous oxide. Or its opposite aluminium oxide to aluminium.

Originally Posted by Dougal

You need to explain this a lot more. The only way you can get a higher EGT with a lower cylinder temp is from a very slow burning fuel. LPG is not a slow burning fuel when compared to diesel..

or as i have now tryed to exsplane twice, sonic pulse overlap, back pressure, fule burning out side of the CCT

Originally Posted by Dougal

Durr..

Originally Posted by Dougal

The stoich ratio for LPG is approx 20:1. It displaces 5% of it's air with a fuel which has a comparatively low energy density..

LPG in this instance is not the fule it is an additive, there fore the stoich ratio is not aplicable as it would be in an LPG powerd motor, you are trying to spin out a red herring here.

Originally Posted by Dougal

No-one is injecting sand (granular solids), only gases and vapourised liquids..

Gases are just solids as is Vapourised liquids, my example stands

Originally Posted by Dougal

The average composition of diesel is around C7H14, as you can tell from the ratio of C:H this is not a typical x2+2 hydrocarbon chain, it's a mix and that's the average.
Cetane is a rating system..

cetane, or n-hexadecane (C16H34), typical of diesel fuel, Cycloheptane C7H14 is also in the mix as is many other C&H molecules, there is no dispute over that. Centane is a rating system it is based on the molecule also known as n-hexadecane. You may regard it as a measure of energy and it is inductive of a measure of energy and is used commonly that way, but it isn’t.

Originally Posted by Dougal

I have no idea where you're going with this or why..

because you asked why it would encourage a cooler burn

Originally Posted by Dougal

Compre the autoignition point of propane with the compression temperatures of diesel. When you've done this tell me why running on preignition is a desirable outcome.

because LPG under pressure will liquefy, the autoiginiton ( interesting word) point I assume you are thinking of is for LPG when its in its Gas state.

Therefore there is no preigntion

Originally Posted by clean32

Wrong there is only one element that burns and there are no chemical or species on the periodic table only elements. Oxidation is a different reaction, like Rust, ferrous to ferrous oxide. Or its opposite aluminium oxide to aluminium.

or as i have now tryed to exsplane twice, sonic pulse overlap, back pressure, fule burning out side of the CCT


LPG in this instance is not the fule it is an additive, there fore the stoich ratio is not aplicable as it would be in an LPG powerd motor, you are trying to spin out a red herring here.


Gases are just solids as is Vapourised liquids, my example stands

cetane, or n-hexadecane (C16H34), typical of diesel fuel, Cycloheptane C7H14 is also in the mix as is many other C&H molecules, there is no dispute over that. Centane is a rating system it is based on the molecule also known as n-hexadecane. You may regard it as a measure of energy and it is inductive of a measure of energy and is used commonly that way, but it isn’t.


because you asked why it would encourage a cooler burn

because LPG under pressure will liquefy, the autoiginiton ( interesting word) point I assume you are thinking of is for LPG when its in its Gas state.

Therefore there is no preigntion

In the face of:
Only hydrogen burning;
lpg not being a fuel;
gases being solids;
gas tuners reducing injection volumes to stop preignition that can never happen;
and oxidation not being burning;

I guess I'm done here.

Originally Posted by Dougal

In the face of:
Only hydrogen burning;.

True, hydrogen and oxogen forms a reaction we call burning. even buring a bit of wood is a hydrogen oxogen reaction

Originally Posted by Dougal

lpg not being a fuel;.

where did you get that from, nothing i wrote

Originally Posted by Dougal

gases being solids;.

all molicules are solids, its just how much space there is between them.
the example i gave is still valid

Originally Posted by Dougal

and oxidation not being burning;.

no its not LOL oxidation is a difrent reaction, though both involve oxigen

Originally Posted by Dougal

I guess I'm done here.

I am sorry if I have disported you as this sites presumed top turbo guy this was never my intention, your practice is sound, your knowledge is good, but your understanding is lacking.
Taking shots at me will not help you to understand more, but more questions will, and i am more than happy to answer any and all as time allows.