Propane sputter

[EclipseTurbo]

I've got the propain kit installed. The I left the reg alone running at natural pressure about 110-120 PSI. 81 Jet (middle). 50% duty.

I set it to come on at 7 PSI. Oops, I think it's too little boost and too much fuel. The car sputtered and hesistated badly. Just a note: my engine is only 2.0 litre and this maybe this is too much fuel. I tried around 30% duty and ran 11 PSI and it still stumbled.

I am still running 100 PSI distilled water injection however, maybe it reacts poorly with propane?

So I decided to turn off the Propane switch and dial in the boost controller to run 14 PSI first.

Shortly after the nozzle nut on my pipe felt off causing a huge boost leak.. and I limped it home. I knew I shouldn't have JB welded the nut onto the pipe. 110 PSI of propane shot the nut with the hose off ... So this time I bring out the welder and do it the right way.

I'm going to install the smallest jet and head out again.

Has anyone got their car to stumble before? And should I take out 5-10% of gasoline?

 

[JayC]

I would remove the water injection and try it that way. Also, how far away from the throttle body are you injecting?

 

[EclipseTurbo]

Propane is between intercooler outlet and upper IC pipe. I figure give it more time to mix.

Water is the TB elbow.

 

[Downtown]

Originally posted by EclipseTurbo
I've got the propain kit installed. The I left the reg alone running at natural pressure about 110-120 PSI. 81 Jet (middle). 50% duty.

I set it to come on at 7 PSI. Oops, I think it's too little boost and too much fuel. The car sputtered and hesistated badly.
Has anyone got their car to stumble before

I think your tank pressure is good if you can maintain that. You probably are having it come on too soon. With smaller jets than I am currently running, I had the propane come on that low on my TR with no problems.

I am running a big jet and having it come on around 15 lbs of boost. Like anything else you do to your car, you have to tune it a bit to make it work for you. There have been several different combinations that worked for me depending on tank pressure, max boost levels, etc.

The stumbling/hesistation is part of the tuning process and pretty easy to correct.

 

[EclipseTurbo]

OK I have welded the 7/16 nut onto the pipe.

And I did some more tests! I used the smallest jet. at first I didn't got any results. Knocking alot and hesitated after I shifted. O2 voltage has increased but did not sputter like yesterday.

I was playing with the solenoid duty, 30-50%. The O2 voltage indicates extra richness from the extra fuel. But I was getting knock anyway?? I started taking out some fuel and it was less boggy.

At one point I turned the solenoid duty to max and suddenly it was surpressing the knock just about completely, a big improvement...

What is the definition of the solenoid duty? Is 50% = pulse open for 500 ms in one seond? I just know 100% made a huge difference.

Oh I managed to kept the water injection on, there is not noticable bogging difference but they work together pretty well.

 

[Turbo__Tim]

Quote by Eclipse Turbo my engine is only 2.0 litre and this maybe this is too much fuel. I tried around 30% duty and ran 11 PSI and it still stumbled.

Best guess here is you displaced too much air with all the propane. You would be running rich.

You are on the right track IMO with the smaller jet.

I tried to combine water/alchy injection with Propane, and got stumble as well. Prolly flooded the plugs. I suggest you tune with the smaller propane jet, and then go to a pure denatured alchy mix with the alchy injection. Not sure, but if you go with a smaller jet there, delay the turn-on point, and basically put as little as possible in, you may find a tiny improvement.

See the thread 'injecting pre intercooler' for more thoughts, ideas, on this. Using both systems is still in the experimental stages....

 

[joereitman]

95GST is having good initial results with WI and Propane together- see last 10 or so posts of the dsmtalk propane thread, which also includes very recent discussion of bogging issues due to injection pre-BOV.

Joe

 

[EclipseTurbo]

Oh I'm 95GST on the DSMtalk BTW.

 

[joereitman]

Originally posted by EclipseTurbo
Oh I'm 95GST on the DSMtalk BTW.

Well I guess I should have known I was not the only dsmtalker lurking about here. You're a sneaky guy Jeremy, with all these different "handles".

Back on topic- your initial disappointing results with WI were when the wire was accidentally disconnected but not yet discovered and the WI was not working, right? And I understand (for the benefit of those participating in this thread) that you now have the WI and propane working well together?

Thanks

Joe

 

[EclipseTurbo]

Well Yes There is no side effects of adding water injection with propane. Mostly, it works to reduce knock before propane kicks in. But consistently less knock overall when both is used.

 

[Turbo__Tim]

EclipseTurbo - I'm glad to see the two sysytems work together. There are not many that have gone this route. I'm guessing that you stayed with the same size water jets? I'm thinking of going smaller in the spring when I resume testing...

Joereitman - It will be great to see the results of your testing!

 

[EclipseTurbo]

Tim, I'm using the same jet as before. Sometimes if I run a little rich I can get a miss. So maybe a smaller jet will make me run smoother.. or I can up the boost instead.

POOR spark plugs have to deal with all these stuff I throw at it

 

[joereitman]

Originally posted by EclipseTurbo
So maybe a smaller jet will make me run smoother.. or I can up the boost instead.

You know which one I vote for.

Jeremy- have you fully modded the MAS to maximize airflow? My 1.25" cold air MAS bypass leaned me out significantly.

Joe

 

[EclipseTurbo]

Originally posted by joereitman
You know which one I vote for.

Jeremy- have you fully modded the MAS to maximize airflow? My 1.25" cold air MAS bypass leaned me out significantly.

Joe

Joe, you forget I have full control over fuel and timing so I do not need to "cheat" the ECU..

One problem now I have is if I get on it, and let off and coast (TB mostly closed) I will smell the propane few seconds later. I believe the BOV releases the air to the turbo inlet and because the engine isn't breathing it, it goes out the air filter. It's sort of embarassing and annoying.

Future plans is still to relocate the nozzle to closer to the TB and after the BOV for sure.

 

[joereitman]

So you don't think a 2nd solenoid at the point of injection will eliminate the line purging affect you are seeing? This seems to work well for me so far. No "embarassing" smells.

Joe

 

[JayC]

Our initial test kits had solenoids close to the injection point. In the end, though, we decided against doing that for the production kits because it keeps propane in the line when the system is off. We wanted the system to be purged from the back to the front when the system wasn't active.

So, while you can add a second solenoid and it will probably help your problem, be aware that it will leave propane in the line when the system is inactive.

 

[EclipseTurbo]

I don't think my problem is from the propane in the lines, it's from the propane already entered the IC piping. The line is AN3(4?) and it's really thin. The injection point is before the BOV so alot of volume already built up when it's ready to vent.

I believe relatively I'm injecting alot more propane than your system, Joe. My differential pressure for the propane is 80-17 = 63 PSI. While you're pre-turbo at 15 PSI or so? Try injecting 60+ PSI and I think you'll smell yours too

 

[joereitman]

Originally posted by EclipseTurbo
My differential pressure for the propane is 80-17 = 63 PSI. While you're pre-turbo at 15 PSI or so? Try injecting 60+ PSI and I think you'll smell yours too

My pre-turbo injection is at either 21 or 22, can't recall at the moment. I wonder whether the vacuum leading to the compressor wheel helps "pull" the propane in at a higher rate and/or greater volume, or whether the regulator precludes that? I am unfamiliar with the internal design of the regulator, but since it accomodates extra flow via turning the valve further open, the pre-compressor vacuum should increase flow, I guess. Seems like it would be hard to quantify though.

Another consideration is that even at lower pressure, I can accomplish fairly substantial flow by opening the valve further. Also, I have no jet inhibiting flow. But, since you have dsmlink and are taking out fuel and I don't have that capacity (except my low tech MAS mods) you are probably running a good bit more propane than I am.

BTW, with enough propane coming out of the intake tract to smell it inside the car, I wonder it that poses a danger? I would not want to see a BBQ'd DSM.

Another thought- I am injecting at the beginning of the intake tract, while you are injecting much closer to the TB. By the time the propane in my system travels to the TB, boost has risen past the hobbs switch trigger point. But in your car and in all the other UICP installations I have read about, the propane is right there at the TB just about as soon as the Hobbs switch activates, before boost has risen much further, maybe causing bogging or sputtering if flow is too great in relation to boost level? However, this assumption only works if the propane travels from the tank to the UICP very quickly- not sure how fast it travels. Now I have confused myself, so I will quit for the night.

Joe