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markrinker
08-09-2005, 18:33
I am interested in hearing what propane injection experience DP members have had with the Duramax, specifically the LLY version if possible.

MSD looks like it has the most 'sophisticated' system on the market, one that monitors engine realtime stats and introduces propane as it sees necessary. Also cuts it off if parameters (namely EGTs) get out of range.

Lower total fuel cost per mile, increased towing range, and additional 'on demand' towing power is what I seek - in that order.

Would ~32 gallons of diesel plus ~30 gallons of propane on board give me ~62 total fuel gallons * 12mpg (low average towing) = or over 700 miles of total range before refilling one or both?

Anyone stacking propane on top of a custom ECM program or power tuner?

More Power
08-10-2005, 13:14
I don't have any experience with propane. The tedious nature of its delivery, plumbing and associated costs have kept by curiosity in check. My current opinion is that power can be better made with fuel/boost.

I read an alternative fuels paper about 10 years ago that indicated that the diesels they tested could run on as much as 75% alternate fuel - whether that be methanol or propane. At least 25% of the power being produced needed to be from diesel fuel to keep combustion somewhat normal for a diesel.

In a situation where propane was abundant and cheap, it might make sense to install a system - simply for the fuel cost savings. For power, I'd stick with boxes/programs.

I know of one Duramax that windowed the block when the device that vaporizes liquid propane stopped working and injected liquid into the engine. :(

Jim

markrinker
08-10-2005, 16:07
It seems like propane technology is lagging way behind - probably because it is marginally cost effective, even in the best of circumstances.

I won't be rushing into anything, but watching what the economics will be if diesel makes another run up in price, as predicted.

If a guy really got serious about it, and sorted out the technology needed, you could buy in bulk and quietly do your own fueling from the BIG tank next to the garage...I like that idea better than processing used veggie oil.

In my very uneducated vision, I see a propane system that only engages when TOW/HAUL is activated, and then only when boost is clearly indicating a load - not sure even what that would be on an LLY... >15lbs?

JoeyD
08-10-2005, 16:26
I have a PS2000 on my truck, I know it's not a d max but it does add milage and power and it was very easy to install. I never used it enough to say how much if any the propane adds to miles traveled vs diesel and propane costs.
The system comes on at a set boost setting that is adjustable. The MSD system looks nice.

Kennedy
08-10-2005, 18:25
The simplicity of the Powershot 2000 is very appealing. Simple, mechanical, and adjustable. You will extend your trip range, but not on a 1 gallon to one gallon rate, not even close. Someone with long term use would be best to suggest how much extra range per gallon of LP consumed will net.

madmatt
08-10-2005, 19:21
I know of one Duramax that windowed the block when the device that vaporizes liquid propane stopped working and injected liquid into the engine.
add a Powerstroke to your list of busted blocks :eek: The only device that quite working though was our brains....we got a little greedy w/ the nozzle size, spooled'er up real good, the propane came on and .....BOOM!!!!Happened so smooth we thought we blew a boot. Shut it down, coasted to the side of the road to inspect the damage and damn, glad it wasn't my truck :D

LanduytG
08-11-2005, 01:34
The PS2K is by far the the way to go. Very east to install, totally adjustable as far as boost and gas flow. The other brands have limitations plus some you have to plumb hot water to vaporize the LP. As far as propane technoligy you can only deliver it so many ways.

Greg

markrinker
08-12-2005, 06:07
I may start with a 'manual' system (no interface to ECM) on one of the 6.5s as an experiment, then upgrade the Duramax based on that experience.

Thanks for the input. If anyone knows of a hauler using propane on either engine, please put me in contact with them. I am very interested in real world towing metrics.

Jim Brzozowski
08-12-2005, 08:16
Hey Mark, get your hands on the latest Hot Rod Magazine, they cover diesels & propane use. Seems like the ratio was 10 gallons of propane for every 36 gallons of diesel on the MSD setup.

king D
08-19-2005, 01:57
i have both a bully dog lp system on the duramx and a powershot on the dodge.i like both systems however i can tune the bully dog to make more power becuase it has greater adjustabilty.i never really used the lp on trips to check for mileage...

Kennedy
08-19-2005, 07:20
The Powershot would be my preference as it is a vapor only system. No coolant lines etc. Just make sure the bottle stays in the correct position so as not to draw liquid...

markrinker
08-19-2005, 16:37
Picked up HOTROD today. Great article on diesel hot rodding!

Diesel Dan
08-28-2005, 04:25
I'd be interested to see what kind of mileage increases one might see also. If all you are doing is running down the highway you would have to see a reduction in the amount of diesel burned. Being that it is getting offset by propane. I have thought about installing it on my motorhome. It is equipped with a 50 gallon LP tank(90 gal. diesel) so I have plenty on board!

Craig M
08-29-2005, 09:22
I thought you needed a reasonable amount of boost for the propane injection to do any good. They say not to install it on no turbo 6.2/6.5's. On flat ground with no trailer the 6.5 has very little boost. Once one hits the hills or is pulling a trailer (fie boost), then the propane could come into play.

Diesel Dan
08-29-2005, 12:17
Reasonable boost?
My dodge cruises at 70mph with 10-13psi. 15-17psi on any small hill.
The motorhome should have boost almost always, pushing a brick down the road and all :D .

Craig M
08-29-2005, 14:21
I do not have a Cummins in any pickups, but stock turboed 6.5's or Banks equiped 6.2's usually only see 2 or 3 psi on level ground with no trailer.

DmaxMaverick
08-29-2005, 18:34
Originally posted by Craig M:
I thought you needed a reasonable amount of boost for the propane injection to do any good. They say not to install it on no turbo 6.2/6.5's. On flat ground with no trailer the 6.5 has very little boost. Once one hits the hills or is pulling a trailer (fie boost), then the propane could come into play. This belief is correct.

The propane will only benefit, both in power and efficiency, if there is sufficient O2 to burn the fuel. If you have little or no boost, the propane will only take up space that should be occupied by O2. If you have boost enough to supply more O2 than can be consumed by existing fuel, you will benefit with propane, first with more power, then with efficiency as the % of O2 to fuel increases.

The propane introduction should be linear with boost. Adding propane at cruising speeds would just waste propane. You won't have a need for increased power, and the economy you gain won't offset the propane used. There just isn't enough O2 to gain efficiency.

The Cummins engines will have more boost, even at cruising speeds. Smaller displacement demands it. If you want more power, with less CI's, you have to get more fuel to burn. Cummins does it by adding boost and fuel, essentially cramming 6.5L's worth of O2/fuel into 5.9L's. Still, there will be a similar power/efficiency gain between the two engines while cruising. The Cummins has more boost because it needs it. There is still the same O2 to fuel ratio to maintain cruising speed.

britannic
08-30-2005, 04:50
The Cummins also makes more power, because it is a DI engine, as opposed to the IDI 6.2/6.5L GM diesel.


Originally posted by DmaxMaverick:
[QUOTE]Originally posted by Craig M:

The Cummins engines will have more boost, even at cruising speeds. Smaller displacement demands it. If you want more power, with less CI's, you have to get more fuel to burn. Cummins does it by adding boost and fuel, essentially cramming 6.5L's worth of O2/fuel into 5.9L's. Still, there will be a similar power/efficiency gain between the two engines while cruising. The Cummins has more boost because it needs it. There is still the same O2 to fuel ratio to maintain cruising speed.