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stovie 09-20-2013 04:10 PM

MPG experiment!!
Ok I'm trying to see if I can run a jeep with no throttle and just using a ball valve to control the amount of fuel(propane!!!) that goes in the engine. I've tryed it on my jeep already, it worked fine but there was some problems with timing and other things cause it was running rather rough. I'm wondering if there's a distributor that does the timing advance by the rpm's of the motor instead of vacuum or computer(I know some vacuum distributors have a centrifugal timing advance if not all of them). I'm also needing a computer that will run the transmission without the other engine sensors cause they'll be removed also(except for crankshaft sensor of course).

chadcmb 09-20-2013 05:12 PM

interesteing. get some video of it running even if it runs bad.

stovie 09-20-2013 09:41 PM

2 Attachment(s)
I'm having trouble with downloading the video so I have some pictures for now, ill hurry and get the video up as soon as possible!!

Attachment 695289

This is my set up from the tank. I have a valve inline so I can fine tune the fuel(note: the propane can hit pressures of about 200 psi so it's not a good idea to open the valve all the way!!! I tested to see how the hose would hold up and it started bulging pretty bad)

Attachment 695313

This is where I attached it. Putting it on the fuel canister line helps to distribute it evenly between cylinders.

I ran it for a bit to try and get a video of it running ,after about 10 minutes the computer advanced the timing to were it backfired pretty good and I had a little six inch flame coming out the intake. I hooked all the sensors back up and it ran better then it did before the propane and idled at about 250 rpm!!!

gmtech22 09-20-2013 11:59 PM

better hope that valve doesn't somehow fail you, end up with a runaway 4.0L

zj97ltd 09-21-2013 09:29 AM

It's interesting no doubt, but jeez that setup sure looks dangerous.

stovie 09-21-2013 12:13 PM

I tried to figure out how much I used to maintain idle and I think I used about 1/4 what my BBQ uses, looking online I found that my BBQ should go 20 hours on a 5 gallon tank so does that mean the jeep should idle for 80??(I know that's not the proper way to figure it out! I had the valve on the tank at 1/4 turn for 900 rpm) Yes it's not safe cause if the valve on the tank is accidentally opened to far the hose will blow!! That's why I went and grabed a pressure regulater to maintain about 3psi I think it was.

Area11 09-21-2013 12:24 PM


Myusername1674 09-21-2013 12:31 PM

Thats my question really, is why do this? hahaha I mean at least it's something different so I don't wanna stop you! By all means go ahead! :PopCorn:

But I would like to know your reasoning behind this idea.

dnuccio 09-21-2013 12:34 PM


xcaliber81 09-21-2013 01:19 PM

Propane Is waaayyyy cheaper than gas and everyone I know that converted to propane were happy. However in the cold whether propane has frozen up also you get less bang for your buck.

zj97ltd 09-21-2013 01:23 PM

If a real propane kit is out of the question, maybe you can find a totaled forklift or something to get LP parts off of.

stovie 09-21-2013 01:27 PM

I was watching an episode of mythbusters and they were talking about needing the proper air/fuel ratio for a explosion with methane gas, that got me thinking that if you have a motor that's compressing everything to a cr of 10-1 then don't you have ten times the air in that space! For gas to burn openly it has to be at 14.5-1 air/fuel so in the end doesn't that 1/10 space of the motor only need to be at 145-1 air/fuel ratio! I looked it up and the air/fuel ratio is important for the reaction of burning to be able to jump from fuel molecule to molecule, so at 10-1 CR in a care your technically at 14.5-1 at compression and 145-1 at BDC.

dnuccio 09-21-2013 06:54 PM


Originally Posted by zj97ltd (Post 16200209)
If a real propane kit is out of the question, maybe you can find a totaled forklift or something to get LP parts off of.

it takes a special kind of stupid to total a forklift :rofl:

xcaliber81 09-21-2013 07:01 PM


Originally Posted by dnuccio (Post 16207089)
it takes a special kind of stupid to total a forklift :rofl:

I was gonna comment on that lmao good luck finding a totaled forklift.

zj97ltd 09-21-2013 07:12 PM

I worked at Home Depot for 7 years. I've seen a couple get jacked up pretty bad lol.

The time now is 10:41 PM.

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