Thread: Custom gas injection??

Originally Posted by Dougal

If lpg didn't pre-ignite, then commercial propane engines like the cummins-westport (note - there is no "g") would be able to run a compression ratio higher than 9:1.
These engines are cummins B series architecture, for dedicated CNG engines they run 10:1 compression, for propane it's 9:1, for diesel it's about double that.

Since your engine is NA, I suggest you run propane into it and show us the 20% power improvement. Remember to record EGT's and how long your engine runs for.

We'll be waiting.

For Gods sake Dougal, will you grow up, i have done my best to explane it for all. in this instance the LPG is an additive, its is such a week concentration that it hasn’t a chance of igniting its as simple as that.
And if you think i am going to drive around with an open BBQ bottle well that’s your problem.
All over SE Asia and northern Europe you will see big rigs with 1/2 doz Gas bottles mounted behind the cab. I would sagest that you expand your horizons with your superior knowledge and travel the world telling everyone that what they have been doing for the last decade and a half is wrong.

quote=long stroke;939856]Looks like a big no no
Start looking for a turbo by the sounds
Thanks for confirming

TIM.[/quote]

Hey Tim
Dont be put off by the massive high jack of the thread. Dougal and Clean32 should take it off the forum next time or pick up the phone hey guys. you were just trying to get an easy explanation.
On the point of trying different things Tim, Eric and I are looking at trying a Hydrogen injection system for a bit of an experiment. Will let you know if it has any benefit at all.

Justin

Originally Posted by DRanged

quote=long stroke;939856]Looks like a big no no
Start looking for a turbo by the sounds
Thanks for confirming

TIM.

Hey Tim
Dont be put off by the massive high jack of the thread. Dougal and Clean32 should take it off the forum next time or pick up the phone hey guys. you were just trying to get an easy explanation.
On the point of trying different things Tim, Eric and I are looking at trying a Hydrogen injection system for a bit of an experiment. Will let you know if it has any benefit at all.

Justin[/QUOTE]

Good point.

some maths
as i understand it LPG seems to give the best results at aorund 20% of what a normal LPG motor would consum and that sounds about correct for the power gains claimed.
so for example at 2000rpm you would need to feed about 4ltr at ambiant per minit of LPG or 1.2 of hydrogen. i would say thats about max, so if your going to have a play i would start way lower than that.
keep us posted on how it all works out. just doint do the BBQ thing

Originally Posted by DRanged

quote=long stroke;939856]Looks like a big no no
Start looking for a turbo by the sounds
Thanks for confirming

TIM.

Hey Tim
Dont be put off by the massive high jack of the thread. Dougal and Clean32 should take it off the forum next time or pick up the phone hey guys. you were just trying to get an easy explanation.
On the point of trying different things Tim, Eric and I are looking at trying a Hydrogen injection system for a bit of an experiment. Will let you know if it has any benefit at all.

Justin[/QUOTE]


Thanks Justin
It would be great to here how you go with the experiment!!
Please let us know.

CHEERS TIM.

Originally Posted by clean32

For Gods sake Dougal, will you grow up, i have done my best to explane it for all. in this instance the LPG is an additive, its is such a week concentration that it hasn’t a chance of igniting its as simple as that.
And if you think i am going to drive around with an open BBQ bottle well that’s your problem.
All over SE Asia and northern Europe you will see big rigs with 1/2 doz Gas bottles mounted behind the cab. I would sagest that you expand your horizons with your superior knowledge and travel the world telling everyone that what they have been doing for the last decade and a half is wrong.

I know you've been doing your best to explain your points, but in doing so you've missed mine completely.

A stock 4BD1 with 265Nm runs an air/fuel ratio around 21 when at sealevel at 20 degrees C.
As it gets warmer that air/fuel ratio drops.
At 18:1 you'll start to get lots of black smoke as local regions inside the combustion chamber run out of air. At 15:1 you'll be completely out of oxygen and there'll be nothing left to burn anything.

In between the 21:1 and 15:1 you'll reach thermal limits where pistons are melting.

The engine is consuming at 2000rpm about 3.3 cubic metres per minute of air. You are advocating feeding it 4.2 cubic metres of lpg?
You've written square metres, I presume that's a simple typo.

I know people in all sorts of places are using propane fumigation, people all over the world use heroin too. Doesn't make it a good idea.
There are some seroius downsides to gas fumigation of diesels, people need to first know about them and understand the risks before they try it.

Originally Posted by Dougal

I know you've been doing your best to explain your points, but in doing so you've missed mine completely.

A stock 4BD1 with 265Nm runs an air/fuel ratio around 21 when at sealevel at 20 degrees C.
As it gets warmer that air/fuel ratio drops.
At 18:1 you'll start to get lots of black smoke as local regions inside the combustion chamber run out of air. At 15:1 you'll be completely out of oxygen and there'll be nothing left to burn anything.

In between the 21:1 and 15:1 you'll reach thermal limits where pistons are melting. .

I do completely understand where you are coming from and there is nothing wrong with your logic, but you think that adding LPG is like adding more diesel or displaces oxygen.

Originally Posted by Dougal

The engine is consuming at 2000rpm about 3.3 cubic metres per minute of air. You are advocating feeding it 4.2 cubic metres of lpg?
You've written square metres, I presume that's a simple typo. .

yes Ltrs not meters or 1.5 % max

Originally Posted by Dougal

I know people in all sorts of places are using propane fumigation, people all over the world use heroin too. Doesn't make it a good idea.
There are some seroius downsides to gas fumigation of diesels, people need to first know about them and understand the risks before they try it.

true but trucks on LPG live longer than people on Heroin do. My point is that this is not new, it’s everywhere and has been for some time. But then Australia has some funny unexplainable things like the price of diesel. Australia is the only country I have ever lived in where diesel costs more than petrol.

Look. This is tedious, can we end the tennis game now.

Dictionary definition of "burn" as it applies to chemistry:

burn
1. to undergo rapid combustion or consume fuel in such a way as to give off heat, gases, and, usually, light; be on fire: The fire burned in the grate.
.
.
.
10. Chemistry.
a. to undergo combustion, either fast or slow; oxidize.
b. to undergo fission or fusion.

MANY things "burn" - even magnesium.

Increasing fuel for the same amount of air will increase temperatures, no ifs, buts or maybes. Regardless of what that fuel is. The increase might not be the same for each fuel, but it will increase.

Originally Posted by isuzurover

Look. This is tedious, can we end the tennis game now.

Dictionary definition of "burn" as it applies to chemistry:


MANY things "burn" - even magnesium.

Increasing fuel for the same amount of air will increase temperatures, no ifs, buts or maybes. Regardless of what that fuel is. The increase might not be the same for each fuel, but it will increase.

No problem with oxidation and burning. But is it always the case that more fuel equals greater temperature? I recall that lean petrol mix causes burnt valves. Is this not due to extra heat which is overcome by increasing the fuel in the mix?