Propane report: Trip 1

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zuluzeugma

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A few guys have asked me some questions about my recent propane swap. I know there are several threads already on it, but I thought I’d add what I learned. I want to be very clear about one thing: In no way is my write-up meant to de-mean or dog propane-guy or got-propane. Both guys have great kits that include everything you need. Saying that, I didn't have $875 (plus $160 for tank) to spend on it and pieced it together myself for a fraction of the cost. Most of you will not get away as cheap as I did, but you can do it for under $500. Don't be scared to use used stuff from Ebay. Propane components can all be re-built for about 5-10 bucks. There’s not a lot to go wrong with them.

Use this formula when sizing your unit: CFM = CID x RPM / 1728 / 2 * 0.95
For me this was between a 225 and a 250. I got a 225 cheap so I went with that.

-Engine: 1F - stock, except for header and HEI
-Evap: Impco Model E with LP line - used for $25
-Carb/rg: Impco 225 with associated vacuum lines - used for $20
-Electronic fuel cut: used for $5
-8 gallon used forklift tank (5 year re-certification): $64
-Tank straps from forklift (found junk forklift in scrap yard): $4.25
-High pressure line from tank to Evap: $57 (this should have been way cheaper but I got about 6 foot too much. Cost was $3 a foot and that included ends.
-HP line to forklift tank fitting: $12
-HP line to evap fitting: $3.60
-Cheap 3" Air filter: $6.78
-I TIGed together an intake that bolted directly to the top of my Webber. That cost me about a dollar in aluminum and an hour of TIG time.
-2ish hours of set-up time

Total: $197.63 and 3 hours

Results: AWESOME. I've have fought and fought my Webber for 2.5 year trying to get it to perform well and have never had much luck. Keep in mind, at this point, my rig is off-road only and I was getting in situations where I was off camber A LOT. Some people have noticed a reduction in power with pane. I noticed an increase in power. It runs at any angle and if it’s hot outside, you can put your face on the tank every once in a while to cool off. I came up with a consumption rate of about 1.5 gallons per hour off road. I feel like a little tuning will get me to more like 1.25 gallons per hour as I was idling high all day Sat. Everyone who has considered fuel injection for off road should re-consider and just do propane.

I'm sure I have forgot some thing so ask any questions you may have. Pictures to follow if anyone cares… My setup looks just like anyone else’s

Flame away...
 
Sounds like a good alternative so what are you doing for fuel cans? Carrying extra tanks sounds like it's gonna be heavy
 
I'm gana buy a second forklift tank when I have coin. I'm also making an adapter so I can run a BBQ Grill tank in emergencies.

Forgot to add: I paid $2.30 a gallon for the pane.
 
So where are the pictures?
 
yes pics and how many miles you getting per tank then, not really practical for daily driver
 
yes pics and how many miles you getting per tank then, not really practical for daily driver

Not true. You can buy larger tanks. I opted out of a huge tank cause mine is an offroad rig only at this point. You can buy a 30 gallon tank. The only reason its not practical for DD is because you have to have propane filling stations all mapped out before you leave on a trip.

How much advance did you give it?

Didn't have a timing light; did it by ear, but I would suspect 15-17 degrees


I'll get some pics up tonight hopefully. Kinda been a retarded week at work and I haven't made it to the shop since Sunday.
 
Ive been back and forth between cng and propane....obviously propane is easier to find....any idea of consumption at sustained throttle...driving down the road?
 
what do CFM and CID stand for? also...where did you get the 1728, 2 and 0.95 values from? sorry for what might seem a stupid question.

also is this for a dual fuel system (LPG/gas) or is it straight propane?
thanks
Use this formula when sizing your unit: CFM = CID x RPM / 1728 / 2 * 0.95
For me this was between a 225 and a 250. I got a 225 cheap so I went with that.
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Ive been back and forth between cng and propane....obviously propane is easier to find....any idea of consumption at sustained throttle...driving down the road?

CNG is awesome but the equiptment is heavier and much more expensive. On a gallon equiv. basis, CNG is 95 cents a gallon right now (given, its in a gaseus state).

Based on mass energy density, propane is 10% less energy dense than gasoline; therefore, you can expect 10% less fuel economy. Heres the caviot: propane is also 110 octane so you can run compression ratios between 11:1-14:1! From thermodynamics, we know the higher the compression ratio, the greater the thermodynamic efficiency. By decking the head and getting the compression ratio up, you can get your 10% back and then some making propane the overall better fuel. The only thing is, once you deck your head that much, if you want to run on gasoline again, you're going to have to buy low-lead aviation gas or race gas. It all depends on what you want to do. I fully intened on building a 2F that runs strictly on propane now after seeing how well it performs.

what do CFM and CID stand for? also...where did you get the 1728, 2 and 0.95 values from? sorry for what might seem a stupid question.

also is this for a dual fuel system (LPG/gas) or is it straight propane?
thanks

CFM = Cubic Feet per Minute
CID = Cubic Inches of displacement (1F = 238ci, 2F = 256ci, 3FE = 244ci)
1728 = conversion factor
.95 = fuel efficiency (use .85 to .95 for carbed engine and a 1 for a fuel injected engine running in closed loop) Basically, engines that are taking 02 infomation in and regulating fuel based on that number are more efficent.

Currently I can flip back to gasoline. However, I plan on building it for straight propane. read above.


I will put pictures up, I swear, its been a tough week.
 
I have been running the 60 on propane for a few weeks now and I really dig it. So far I have been getting like 11.5mpg.

I set my timing at 15deg with the vacuum advanced blocked off. I also experienced a power increase but I think I'm running pretty rich until it gets warmed up.

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just throwing this out there. just wondering as I don't know.

when you buy the propane do you pay road taxes on it?? same question with natural gas?

is that the same as using dyed deisel on road??
 
just throwing this out there. just wondering as I don't know.

when you buy the propane do you pay road taxes on it?? same question with natural gas?

is that the same as using dyed deisel on road??

Essentially yes. Until America gets off its lazy ass and catches up with Europe and the rest of the world with roadside LPG and CNG filling stations, we won't be taxed on the fuels. It is kind of like running "red diesel", except there is no dye, so there is no evidence and therefore no way to get in trouble. Just tell the cop you're trying to be more environmentally friendly and he'll let you loose.

As a side note: 25% of all vehicles are running on CNG now in Europe.

Personal feeling: The first American car company to invest money into infrastructure for LPG and CNG and then builds cars to run on those fuels will be one of the only American car companies to survive. This may come as some joint deal, i.e. (Shell and Ford) or (BP America and Chevy). If the car manufactures take on some of the capital costs, it will happen faster. As mentioned, CNG is about 90 cents a gallon on an equivalent basis right now.
 
As mentioned, CNG is about 90 cents a gallon on an equivalent basis right now.

Jump on it quick then! ;)

The law of supply and demand will push the price right up there with gasoline. :rolleyes: They have to pay for that infrastructure somehow. :D
 
Jump on it quick then! ;)

The law of supply and demand will push the price right up there with gasoline. :rolleyes: They have to pay for that infrastructure somehow. :D

Probably not...

In the last two years, horizontal drilling has made a ton of previously impossible shale plays attractive for oil and gas companies in today's nat. gas market. If anything, nat. gas will go down rather than go up based on an over abundance of supply. Boone Pickens has got it right...
 
Shoot Nat gas ought to be cheaper considering the amount of wells just here in South TX. Funny thing is most of the wells we work down here are drilled for CNG and the "Oil" that comes out of them is bi product. Unfortunately they aren't giving it away. My boss and I have asked.
 

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