World First (most likely)

[marlin1111]

Modification of Interest to the CRD Owners!

I have just completed installation of LPG Injection system to my CRD V6 to increase the burn efficiency of the deisel motor from 75% to 95%

Outcome, more power, better fuel economy, cleaner running, less soot, more go, cleaner oil. The LPG is injected right at the inlet to the turbo as a vapour & begins flowing at 4 pounds of boost & increases flow to around 10 % of the fuel mixture @WOT.

Installed a 30 litre LPG tank in the trunk, which should last for 3 tank fulls of diesel depending on driving style. LPG fill is behind the number plate, so no extra holes!

I will be doing a 700 km trip tomorrow & will then have fuel economy figures. After Easter I will be doing Dyno & emission testing to get the real facts & figures & will Post.

Other mods: 22 in, lower 1.5 inches, 800 watt amp & sub, full 6000K HID lighting inc. fogs . Preformance Chip, Blacked out tails, Grill, Turbo Boost gauge, LPG tank level gauge. GPS integrated to mobile!

Marlin1111

[Rambit]

Sounds interesting Marlin. Keep us updated!!!

Bernie

[Columbo]

I have a buddy who did this mod to his Ford Excursion and he saw a 50% increase in gas mileage, and would routinely smoke mustangs from light to light! The difference in power and economy was unreal.

I hope you have the same, or better results.

[badger]

This has been tried in the UK with varying levels of success.

The first option is for large truck fleet companies, their diesel truck engines have the electronic fuelling map altered to remove about 20% of the diesel going into the engine, then the gas (LPG, Propane) is added (via a programmed injection system) to compensate for the drop in performance and yes, this provides a much cleaner burn. Only about an 8% LPG addition is required to restore performance of the 20% diesel removed. Overall, this suits large fleets with their own depots as they can have their own tanks etc, buying LPG in bulk is a lot cheaper as well. Savings of around 10% overall are possible, which is a LOT of money to a fleet owner of, say, 20 lorries. Payback times are quick as well, due to the massive mileages covered by these fleets.

Second option is to add LPG at the turbo inlet as a power boost, much in the same way that a petrol engine would utilise nitrous oxide. Emissions are only lowered IF there is an excess of free oxygen after diesel combustion has taken place, to enable a full and complete burn, otherwise emissions are worse! The major downfall to this system is that it is filling the turbo, intercooler, pipework and manifold with a highly explosive air/propane mix, and should anything ever go wrong like a burnt out inlet valve, say, then there's gonna be one almighty kaboom! Another downfall is piston ring land failure on the pistons themselves due to increased pressures and burn temperatures. This type of system is actually referred to as a "fumigation" system. I did a lot of work on a landrover discovery TDi with one of these systems that was being used as a rally car, it ran 2 bar turbo boost, added LPG above 1/2 throttle and was, in all honesty, gutless! The engine was well down on power when running on diesel alone, caused by the original power increase stressing the engine highly and the piston rings lost their "springiness" due to the higher combustion temp which in turn gave rise to a massive loss of compression and reduced power. It only lasts for so long, then the damage is permanent!!

Here's a link to the LPG conversion I've just done on my Hemi, for those that may be interested. Pictures are on page 2.
LPG conversion on 5.7 Hemi

[marlin1111]

Hi Badger: interesting the 5.7 on LPG, what happens when the ECU shuts down cylinders or the RPM limiter cuts in & the gas keeps flowing??. I did a 100 series Landcruiser 4.5 petrol Super Charged on LPG & had to by pass the rev limiter so I did blow the head off the car when the spark stared again!!
I know what you mean about drilling holes I put a 2 inch hold in the trunk to feed the lines & wires in!!!

Re: "Worlds First" This conversion is quite common on truck & 4WD vehicles but I would imagine the first on a 300 CRD, hence the Post's title.

Gas flow is controlled by Turbo boost via a pressure sensitive valve. Only vapour is drawn from the tank at low pressure. Earlier systems used liquid LPG like for regular petrol cars & required convertors & water to stop freezing & were mored complicated & prone to problems.
On testing exhaust temps are down.
At 100kph (60 mph) steady throttle, flat road, I am running around 4 pounds of boost which is the point where gas is beginning to flow. I notice I need less throttle to maintain speed (you can see this when the system is turned on or off from the Throttle Indicator on the service screen in the dash. Pick-up is improved & responce is improved, it loves hills & load & pulls like a train! With traction contol off it will spin the wheels off the make, where before you might get a squeak!! I have 700 klms ahead of me in a few hours, I usually burn 54 to 56 litres of diesel for the trip, so I have a good reference. I have also changed the oil & will be interested to see what it looks like after 700km. Using this same system a Kenworth truck is saving around A$1000 a month off his fuel bill & pulling taller gear up most hills! A friend of mine with a deisel 80 series Toyota Landcuiser has picked up 15 km higher top speed!

Regards marlin1111

[badger]

Hi marlin1111, the lpg system fitted to the Hemi is a sequential injection "master and slave" type of setup, so the gas simply emulates whatever the petrol does, same when in MDS mode or for a rev limiter as both these functions are controlled by the stock ecu simply shutting off injector pulses. (MDS does more, but the fuel side is simple, it simply stops pulsing current to injectors 1,4,6 and 7)

All the diesels I have encountered here in the UK with LPG have been liquid phase offtake from the tank and had vapourisers. I must admit to not being wholly up to speed with current developments in the diesel/lpg field as that isn't something that is very popular in the UK, at the moment.

[marlin1111]

Hi Guys:
work is still in progress & install bugs have been sorted. I will be doing Dyno & EPA (emission testing) in the next week or so. Initial power is up & it pulls much harder in the upper gears. I havn't do an economy check yet & will do after the system is tuned to the car after dyno work. All up looking good.

I hear the CRD is now available in the USA, is this so???

Marlin1111

[propus]

Originally Posted by marlin1111

Hi Guys:
work is still in progress & install bugs have been sorted. I will be doing Dyno & EPA (emission testing) in the next week or so. Initial power is up & it pulls much harder in the upper gears. I havn't do an economy check yet & will do after the system is tuned to the car after dyno work. All up looking good.

I hear the CRD is now available in the USA, is this so???

Marlin1111

Marlin,

Any update on the performance of your CRD LPG conversion?

[wildmark]

If the cost of gas keeps going up here they should consider selling the CRD here!!!!

[RTP SRT8]

I don't know too much about the CRD. I don't think they are available in the USA.
I was just reading about the LPG upgrade to the Diesel motor, which I guess is a V6 turbo?
Then somone chimed in about a LPG system for a 5.7 hemi?
Can somone clear this up for me? We on the West side of the pond just don't get the diesel thing. I would love to see a Diesel 300 or european 300C.
What other differences between the USA cars and the European cars are there? Do you in Europe wish you had an American model that is not available to you???
I have heard of people all over the world with 6.1 hemi SRT8's, why can't we get a Diesel over here??