Author Topic: Propane injection. (Read 9215 times)

foxracer1 · « **on:** October 18, 2006, 12:38:51 pm »

So i've been thinking about propane injection. Most all of the systems that are sold aftermarket are vapor injection. Why inject liquid propane into the airstream after the turbo to 1. provide propane of course and 2. provide a cooling effect on the ingested air? I'm unsure how to properly inject liquid LPG. At what quanity etc. does anybody have any ideas? please let forth your knowledge.

malone · « **Reply #1 on:** October 18, 2006, 12:41:08 pm »

A good read, to start with:
http://www.mrsharkey.com/lpg.htm

foxracer1 · « **Reply #2 on:** October 18, 2006, 02:11:29 pm »

Thanks malone that will be some interesting reading let me look through it.

foxracer1 · « **Reply #3 on:** October 18, 2006, 02:43:23 pm »

That link is very informational. Thank you very much. That gives me so much more to work with. But it still leaves me curious about using the liquid instead of vapor. I'll continue to investigate this subject and read over that page more an more. Please add anything you guys know or feel.

Kantdrive55 · « **Reply #4 on:** October 20, 2006, 12:39:29 pm »

I would go with water/methanol injection way before propane. You are going to get more power and it drops your exhaust gas temps. Snow performance makes great kits. I am going to be putting a kit on my 93 in the new year.

DVST8R · « **Reply #5 on:** October 20, 2006, 01:27:18 pm »

There have been a few of us that tried the 'pane route back in the old hostboard days. The problem with idi motor's in genral is that they use a really high cr of ~23:1 which causes detonation problems with propane. Even with good setups the most power that gusy gould pick up is only about 10hp before detonation would start. Fspgtd popped at least one head gasket as did joegtd. In short it works as an alternative fuel source far better in a DI motor then in an IDI motor.

Finally adding propane to the car is just like adding more fuel as that is what it is a fuel. We havnt hit the max fuel of these pumps yet so I see no need for it at this point (high rpm apps aside, you know who you are...

) Water/ meth, N20 or a bigger turbo / twin turbo's are all things I would have before doing propane again.

moosiah · « **Reply #6 on:** October 20, 2006, 01:41:28 pm »

my question about propane relates to mileage. I've read that small amounts of propane increase mileage by increasing the total percentage of fuel burn from 75-80% to 97% or so...... I've seen this done w big fords an' dodge'ms , going frm 14mpg to 24mpg in one case......

of course y m m v depending on how heavy yr foot is ...... ( govt required discaimer :roll: )

macsdub · « **Reply #7 on:** October 21, 2006, 12:19:22 pm »

Quote from: DVST8R

There have been a few of us that tried the 'pane route back in the old hostboard days. The problem with idi motor's in genral is that they use a really high cr of ~23:1 which causes detonation problems with propane. Even with good setups the most power that gusy gould pick up is only about 10hp before detonation would start. Fspgtd popped at least one head gasket as did joegtd. In short it works as an alternative fuel source far better in a DI motor then in an IDI motor.

Finally adding propane to the car is just like adding more fuel as that is what it is a fuel. We havnt hit the max fuel of these pumps yet so I see no need for it at this point (high rpm apps aside, you know who you are... ) Water/ meth, N20 or a bigger turbo / twin turbo's are all things I would have before doing propane again.

haahaa yea its not good on an idi,comp ratio is too high
and propane is violent too,try nos or water/meth

lol this happened yesterday...
i was really low on fuel,and i was like 5 miles from the station,i could tell cause it was laying down when i exited curves
so i just pulsed my shifter mounted switch for my water/meth injection
al l the way to the station
on flats i was ok,but id pulse it a little to make it up a grade+hold speed
worked great,like it always has.....

stewardc · « **Reply #8 on:** October 22, 2006, 05:05:26 am »

1. Very little propane is used in propane injection. It's not used as a fuel, it's a fuel enrichment (enhancement) system which boosts the heating value of the primary fuel. Too much is NOT better. The amount is critical.

2. Propane liquid expands 270 times when converting to vapour. (1 cu. inch of liquid = 270 cu. inches of vapour). I think you can see that such a small amount of liquid would be injected that it would be almost impossible to gauge accurately and also that small amount would cool very little.

Fellas, I'm a gas inspector and I can tell you it's not something to fool with lightly. One mistake and BOOMMMMMM !

macsdub · « **Reply #9 on:** October 22, 2006, 07:33:23 am »

i can back ya up,being that ive worked on many propane fueled+natural gas fueled engines
yea ya dont exactly wanna be smokin ciggies near the stuff..........

foxracer1 · « **Reply #10 on:** October 23, 2006, 12:05:58 pm »

Yes im taking alternative fuels here at my school and we are talking about all the hazzards involved with these fuels. But i would still like to try it.

3play · « **Reply #11 on:** October 23, 2006, 10:49:16 pm »

Quote from: foxracer1

Yes im taking alternative fuels here at my school and we are talking about all the hazzards involved with these fuels. But i would still like to try it.

I am on a bus list (greyhound, detroit 671 diesel) and some of the guys run propane for extra power on the hills, you need a pyrometer to figure out the mixture ratio. The temp should slightly go down, when it starts going up, you are adding too much. If you run propane constantly, you need a tank with enough surface area to keep up with the evap. rate, or you need a heating assembly designed to turn the liquid to vapor before it gets to the intake.
The process that really interests me is water emulsion. The big mining companies use this on large diesels, they mix up to 45% water with the diesel fuel and burn it. If the water is in 5 micron droplets or smaller, it becomes steam as the fuel detonates. There are automotive kits available, but you have to re-plumb so the un-used emulsion recirculates through the emulsion pump, so the water doesn't separate. You have to shut off the water a few minutes before stopping, or it will separate while stopped.
The mining equipment runs 24/7, so they just let the whole mess recirculate constantly.....

M.Mech
81 diesel rabbit
85 300 TD
57 GMC PD 4104 Greyhound bus.

foxracer1 · « **Reply #12 on:** October 24, 2006, 10:31:54 am »

Quote from: 3play

Quote from: foxracer1
Yes im taking alternative fuels here at my school and we are talking about all the hazzards involved with these fuels. But i would still like to try it.

I am on a bus list (greyhound, detroit 671 diesel) and some of the guys run propane for extra power on the hills, you need a pyrometer to figure out the mixture ratio. The temp should slightly go down, when it starts going up, you are adding too much. If you run propane constantly, you need a tank with enough surface area to keep up with the evap. rate, or you need a heating assembly designed to turn the liquid to vapor before it gets to the intake.
The process that really interests me is water emulsion. The big mining companies use this on large diesels, they mix up to 45% water with the diesel fuel and burn it. If the water is in 5 micron droplets or smaller, it becomes steam as the fuel detonates. There are automotive kits available, but you have to re-plumb so the un-used emulsion recirculates through the emulsion pump, so the water doesn't separate. You have to shut off the water a few minutes before stopping, or it will separate while stopped.
The mining equipment runs 24/7, so they just let the whole mess recirculate constantly.....

M.Mech
81 diesel rabbit
85 300 TD
57 GMC PD 4104 Greyhound bus.

Thats quite interesting. I have never heard of the water emulsion. I would like to look in to that.

Zeitgeist · « **Reply #13 on:** October 28, 2006, 07:45:46 am »

It's interesting to read that some of you have had problems running propane in your IDI engines. I recently snagged a used Powershot 2000 kit off of ebay for cheap, and it's dropped my 0-60 times from 8.07 to 7.30secs. But, I get some knocking at full boost/WOT. I clearly need to reduce the max fuel flow to reduce the knocking, or else, eh?

I'm curious to learn which type of propane metering system folks were using when they previously experienced problems. Apparently Powershot is one of the few (only?) commercially available systems that meters the flow of propane based upon the amount of boost present. Anyone know if this is true?

foxracer1 · « **Reply #14 on:** October 28, 2006, 08:42:07 am »

Quote from: Zeitgeist

It's interesting to read that some of you have had problems running propane in your IDI engines. I recently snagged a used Powershot 2000 kit off of ebay for cheap, and it's dropped my 0-60 times from 8.07 to 7.30secs. But, I get some knocking at full boost/WOT. I clearly need to reduce the max fuel flow to reduce the knocking, or else, eh?

I'm curious to learn which type of propane metering system folks were using when they previously experienced problems. Apparently Powershot is one of the few (only?) commercially available systems that meters the flow of propane based upon the amount of boost present. Anyone know if this is true?

I would say that it is much better for the engine to ingest it in proportion to boost. Sounds like a good kit. But does anyone know of a liquid injection kit?

Author Topic: Propane injection. (Read 9215 times)

stewardc

3play