Poor mans propane setup, help needed

[patracy]

Originally Posted by tigerfalcon50

I was actually just looking to tap it into the air intake tube and then have a switch so I can turn it on and off when I hit the highway. From what you guys have experienced, is it better to put the propane in before the turbo or after? If this gets too complicated, I'm just gonna say screw it and buy a motorcycle.

This isn't complicated. You DO need the pressure switch. You don't want the propane on when you've lifted off the throttle. The hobbs switch isn't hard to install. Just use the factory tap like me.

You'll need the following...
Propane tank
Adjustable propane regulator (I got mine from tractor supply $20) or a cutting torch regulator.
1/4" solenoid (from ebay $30)
Hobbs pressure switch ($20, also from ebay)
a few 1/4" sections of pipe
1/4" tee
Reducing plugs
Hose
2 1/4" NPT to hose barb
Hose
A bung or something to thread the other nipple in.
fender washer
lock-tight
hose clamps
16ga wire
switch
indicator light
switch mount (if you don't want to put it in your dash)
fuse link
screws
tie wraps
electrical tape
terminal connectors
splice connectors

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1999 2500 4x4 Club Cab Sport. ADRENALINE/pulse BHAF, full set of gauges, FP light, Holley Blue pump, 1/2" big line kit, Draw straw, 3" glasspack, TC lockup switch, Stealth VP plate, Heated WVO setup, poor man's 'pane setup, BD TC, BD VB, Billet input, Derale pan.
Parts to come: 150hp sticks, turbo, and bigger exhaust.

[hipsi]

Are you running the solenoid as close to the injection point as possible or as closer to the bottle valve?

It would make sense to me to have the shut off soleniod right at the injection point which will allow almost instant cut off of gas when you dump the throttle.

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01.5 Flame Red 3500 DRW 2WD LB QC Laramie
09 SRT8 Challenger *On Order*

47RE, 55 Block, BHAF, 4" Rapid Flow, DNA Muffler A.R.E Z Series Cap, Optima Blue Tops, AMSOIL, Anti Spin Diff, Line-X, Mopar Brush Guard, Silverstars, 235/75R/16 Dunlop Rover RVXT, Brembo Brakes, XZT+, RV275's, ISSPRO EV's Trans, Turbo, Fuel.

[patracy]

I've got mine right at the tank. But it'd be better to install it right at the injection point for instant on/off.

Only problem is you'll get fluctuated pressures going into the engine since the hose can expand. You might get a harder "hit" than expected. I did get a bark at low speeds when I tried running my setup. So I only use it at highway speeds now. (Not in traffic)

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1999 2500 4x4 Club Cab Sport. ADRENALINE/pulse BHAF, full set of gauges, FP light, Holley Blue pump, 1/2" big line kit, Draw straw, 3" glasspack, TC lockup switch, Stealth VP plate, Heated WVO setup, poor man's 'pane setup, BD TC, BD VB, Billet input, Derale pan.
Parts to come: 150hp sticks, turbo, and bigger exhaust.

[hipsi]

Makes sense.. did you ever think of another regulator before the injection point to stop pressure creep?

__________________
01.5 Flame Red 3500 DRW 2WD LB QC Laramie
09 SRT8 Challenger *On Order*

47RE, 55 Block, BHAF, 4" Rapid Flow, DNA Muffler A.R.E Z Series Cap, Optima Blue Tops, AMSOIL, Anti Spin Diff, Line-X, Mopar Brush Guard, Silverstars, 235/75R/16 Dunlop Rover RVXT, Brembo Brakes, XZT+, RV275's, ISSPRO EV's Trans, Turbo, Fuel.

[patracy]

Not really. But thinking through it, the way to "fix" this would be to leave the reg at the tank. Then use hardline tubing (Alum is the cheapest) to the engine. Then install the solenoid. Tuning two regulators would probably be a pain.

__________________
1999 2500 4x4 Club Cab Sport. ADRENALINE/pulse BHAF, full set of gauges, FP light, Holley Blue pump, 1/2" big line kit, Draw straw, 3" glasspack, TC lockup switch, Stealth VP plate, Heated WVO setup, poor man's 'pane setup, BD TC, BD VB, Billet input, Derale pan.
Parts to come: 150hp sticks, turbo, and bigger exhaust.

[mailman1175]

Originally Posted by patracy

Not really. But thinking through it, the way to "fix" this would be to leave the reg at the tank. Then use hardline tubing (Alum is the cheapest) to the engine. Then install the solenoid. Tuning two regulators would probably be a pain.

Hardline tubing is what I've been thinking of. Some of these guys are already using two-stage pressure regulation. Why not separate stage one from stage two? Say, put a 10 psi regulator at the tank, then put the adjustable, lower pressure regulator in at the injection point, just ahead of the solenoid.

The downside that I see right off the top of my head is that, with a greater distance between regulators, the odds of you having a 10 psi leak are much greater than those of having a (for example) 3 psi leak. So the chances of emptying your tank before you know it are better. The upshot seems to be that you greatly decrease the effects of temperature fluctuations.

Even with aluminum (or brass, I suppose) tubing, you're going to have temperature affecting pressure in the fuel line. The expansion of rubber lines with the vapor really isn't the issue; it's the increased volume that comes with the higher temps. That's why you probably do want your regulator as close to the injection point as possible.

My old boss had 3 different gasoline-engined trucks that he converted either to run solely on propane or dual-fueled, propane and gasoline. In all cases, the regulators were very close to the point where the fuel was to enter the cylinder (two carbureted engines, one fuel-injected). The concepts of adding propane to diesel fueling and running a gas engine on propane alone are, of course, fundamentally different, but the "over-fueling due to pressure/volume/temperature fluctuations" would seem to have equally undesirable consequences in both types of engine.

This is all just so much thought and theory to me at this point, though. That's where it'll have to stay until I can, A) be convinced of enough cents/mile savings to make the experiment worthwhile, and, B) get some money scratched together to attempt said experiment. So, if any of you guys who're actually doing this have experience which refutes my ramblings, please feel free...

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'94 3500 DRW 4x4; auto; 4.10 gearing; 10' flat bed; BHAF/heatshield; FBD budget 5" TBE w/ cat delete

[patracy]

Couple of pages back I posted up my results. 29mpg. Honestly I'm giggly about it. I've hated this truck until that.

Simply put, if a tank of propane will last a tank of diesel. I'll spend $140 to go 1K miles. It would have cost $205 on diesel.

__________________
1999 2500 4x4 Club Cab Sport. ADRENALINE/pulse BHAF, full set of gauges, FP light, Holley Blue pump, 1/2" big line kit, Draw straw, 3" glasspack, TC lockup switch, Stealth VP plate, Heated WVO setup, poor man's 'pane setup, BD TC, BD VB, Billet input, Derale pan.
Parts to come: 150hp sticks, turbo, and bigger exhaust.

[HBMegaCab]

I am very intrigued by your setup. Do you know if this could cause issues on a stock 2008 6.7? I assume that this has no effect on the DPF or Cat. Any comments appreciated!

[Challenger]

Is the teflon type tape that gas fitters use, yellow or white? Shouldn't this testing be on something disposable like a DURAMAX!

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96 Dodge CTD 3500 4x4 black extracab dually auto 3.54 no mods 1980 Mack Cruise-Liner Cummins N14 370/430 hp 10spd,air ride

[patracy]

Originally Posted by HBMegaCab

I am very intrigued by your setup. Do you know if this could cause issues on a stock 2008 6.7? I assume that this has no effect on the DPF or Cat. Any comments appreciated!

I wouldn't think it'd do anything bad. Might even clean up the DPF or reduce the time it fills.

__________________
1999 2500 4x4 Club Cab Sport. ADRENALINE/pulse BHAF, full set of gauges, FP light, Holley Blue pump, 1/2" big line kit, Draw straw, 3" glasspack, TC lockup switch, Stealth VP plate, Heated WVO setup, poor man's 'pane setup, BD TC, BD VB, Billet input, Derale pan.
Parts to come: 150hp sticks, turbo, and bigger exhaust.

[patracy]

Originally Posted by Challenger

Is the teflon type tape that gas fitters use, yellow or white? Shouldn't this testing be on something disposable like a DURAMAX!

Yellow. I've switched the tape on my setup as well.

Why would you test this on a duramax? It wouldn't need it unlike the cummins.

__________________
1999 2500 4x4 Club Cab Sport. ADRENALINE/pulse BHAF, full set of gauges, FP light, Holley Blue pump, 1/2" big line kit, Draw straw, 3" glasspack, TC lockup switch, Stealth VP plate, Heated WVO setup, poor man's 'pane setup, BD TC, BD VB, Billet input, Derale pan.
Parts to come: 150hp sticks, turbo, and bigger exhaust.

[mailman1175]

Originally Posted by patracy

Couple of pages back I posted up my results. 29mpg. Honestly I'm giggly about it. I've hated this truck until that.

Simply put, if a tank of propane will last a tank of diesel. I'll spend $140 to go 1K miles. It would have cost $205 on diesel.

I've seen your posts on fuel economy. I guess I just misread your interpretation of your results. For some reason I felt like you were hedging just a little bit, as if you were still in the preliminary stages of testing. So I hadn't really tuned in to your economy results yet. You know, too, that all trucks are different. My truck is equipped somewhat differently from yours, and my driving habits are different (daily driver, <60 mph, 35 miles one way), so it's almost impossible to extrapolate from your results. If I saw a 1 -3 mile/diesel gallon increase in fuel economy, it wouldn't really pay to run propane. I'd need at least 5 mpdg, and would prefer to see something more along the lines of 6 - 8. My cost per mile is about 25 cents right now. I'd really need to knock a nickel or better off that, but my calculations tell me that's going to take a pretty good chunk... something like 1 extra mpdg = 1 cent/mile.

If I see the kind of mileage gains you've seen, though, no doubt: I'd be giggly, too.

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'94 3500 DRW 4x4; auto; 4.10 gearing; 10' flat bed; BHAF/heatshield; FBD budget 5" TBE w/ cat delete