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IS Diesel-Gas WORTH IT???
Posted: Mon Jul 21, 2008 7:43 pm
by Dalluke
What do people think of it?
Quote: $4500.00 (kit) + $200 (Exhaust modification to fit tank) + $180 for dyno tuning.....
With government rebate of $2000 = $2880.00 cost to me
They say 25% more economy and 30% more power and torque.
Anyone done it? What do people think about cost effectivness etc....
I have a 2.5L TD 1992 Pajero, they reckon they did one 2 weeks ago and results were really really good, no longer sluggish and no smoke and better economy???
Posted: Mon Jul 21, 2008 8:14 pm
by -Scott-
Define "better economy" - is that purely savings on diesel, or is that taking into account the volume (and cost) of LPG which is used?
Ask for specific figures for both diesel and LPG usage, then do some sums yourself.
Posted: Mon Jul 21, 2008 9:24 pm
by Dalluke
Better economy = more k's for your buck
They say 120L diesel = 650kms = $226.80 (diesel 1.89)
120L diesel + 20L LPG = 850kms = $226.80 + $13.60 (0.69 lpg) = $240.40 for 850kms on Diesel Gas
To get 860kms on diesel you would need 156.9L = $296.55
= $56.10 savings = 23% more economy
Posted: Mon Jul 21, 2008 9:54 pm
by -Scott-
120l for 650km? I have a 120l fuel tank, and that gets 800km from my V6, with 33" tyres and 5" of lift. Do you really use that much fuel?
I'm not doubting that cost savings are available, but I don't like those calculations. You should be getting better than 850km from that 120l of diesel, without the LPG.
Well tuned (injectors done, pump overhauled & properly timed) your vehicle should be capable of getting close to 1000km from that 120 litres. Add 20 litres of LPG, and I would hope you could get another 200km (as they suggest.) But the savings won't equate to 23%.
Posted: Tue Jul 22, 2008 8:43 am
by NJV6
Do a search and see what you come up with. Makes interesting reading.
Spend your money on a 3.2Did...
Imagine how quick a 2.5 would go pop with an extra 30% power! You would have to be very careful driving it as exhaust temps would get out of control pretty quick which is not desirable particularly on a motor with an inherently weak head.
From what I have read the only advantage is the extra power. The fuel useage is about the same when LPG use is taken into account.
Posted: Tue Jul 22, 2008 11:49 am
by Dalluke
Yeah I only get 650kms max from my tank... i think its 120L on the diesel 2.5L although it may only be 100L. Anyone know what they should get??? If i missing out on like 350kms i wanna know.. and how do i fix it!!!
Diesel gas people say they have 3yr warranty and never had probs with 2.5td pajeros, i understand they wanna get my business but i cant find any reports of any failing anywhere?
Thanks for the input to guys, i not trying to preach that this is the way to go i just interested and want to get people opinion.. hehehe
By the way how do you get your 5" lift with IFS or do you have SAS in the front of your paj scott? How much body/suspension etc...
Posted: Tue Jul 22, 2008 12:11 pm
by Dexter
Dalluke wrote:
By the way how do you get your 5" lift with IFS or do you have SAS in the front of your paj scott? How much body/suspension etc...
Pretty sure it would be a 2-3 inch suspension lift and maybe 2 inch body lift.
Posted: Tue Jul 22, 2008 1:11 pm
by NJV6
If you have a std diesel tank then it is 92 litres.
I'd get 650km from 120L in my thirsty beast - thats 20l/100km.... I could tow a caravan everywhere I went and still get better than that!
Either your figures a wrong, your car is sick or there is a hole in the tank.....
Posted: Tue Jul 22, 2008 1:26 pm
by fazza81
I to have been looking at this for a while now. I came up with, How long are you going to keep the pajy? I think you will need atleast 2 or 3 more years out of it before you break even and start saving money.
I have a 2.8td lifted, 31's, rear draws and 2.5 inch exhuast I get 1000k's out of 125L of diesel highway or around town (not towing).
Towing my camper about 800kg I get 12.5L at 100ks on the highway and 14 around town and 15 on fraser.
In short I could not justify the cost as NJV6 said I am looking at upgrading to a Did triton in under 2 years.
Posted: Tue Jul 22, 2008 4:04 pm
by Dalluke
650kms from 92L standard tank 14.1L/100kms --- Do i have a problem???
Going to keep car for a long while, until my wife lets me get a new one, could be years.... hehehehe
Plans to build camper trailer and do australia so not giving it up too soon...
I getting the vibe that it may be too costly for any value... hmmm keep comments coming its very interesting.
If you want info go to
www.dieselgas.com.au
Posted: Tue Jul 22, 2008 5:01 pm
by corkhead
why dont you "dalluke" ask them for a demo in a similar car, maybe get them to contact you next time they service a similar pajero as yours so you can see what it is like.
Posted: Tue Jul 22, 2008 7:03 pm
by -Scott-
Dexter wrote:Dalluke wrote:
By the way how do you get your 5" lift with IFS or do you have SAS in the front of your paj scott? How much body/suspension etc...
Pretty sure it would be a 2-3 inch suspension lift and maybe 2 inch body lift.
Sorry - could have explained at the time. The body sits approx. 5" higher than stock, from 2" body lift, 2" (or more?) suspension lift, and another inch from 33" tyres.
650km from 92l is less than I would like from a diesel - most of the time I can get better than that from my petrol, but, doing trips, I budget for 15l/100km (on road - up to 20l/100km offroad).
I would have thought you could get better those figures from a well tuned 2.5 - and you should really make sure the existing setup is running well, to get the best result when they throw your truck on the dyno.
Have you had some quotes for an injector service & pump overhaul?
Posted: Wed Jul 23, 2008 8:55 am
by Dalluke
No i havent only bought it about 2 months ago, i will go get it checked out me thinks.... thanks guys...
Posted: Wed Jul 23, 2008 9:10 am
by Dalluke
Just had it quoted @ $840 from Sydney Diesel Centre, might have it looked at before i go and spend way more money on gas...
Posted: Wed Jul 23, 2008 5:16 pm
by Vman
Unless your doing a lot of touring I cant really see the value in diesel gas at present.
I get just under 1000km highway driving and average about 800km to a tank around town. I know it could be a tad better with an injector service and tune as it does blow a bit of diesel smoke.
The problem I see with diesel gas is you need to consume both fuels unlike duel fuel petrol where either one or the other is used.
I think converting to say a direct injection common rail engine would have many more benefits than diesel gas - as its pretty expensive for what it is really.
Posted: Wed Jul 23, 2008 5:40 pm
by 4runna
Hey Guys,
I've just finished looking at this myself, and the numbers looked good, but I was mainly wanting the power for my heavily laden Paj. Mine is the 2.8tdi and I get 12/100 round town and 14>15/100 on the highway due to the weight/wind resistance/revs at 110k.
Diesel gas looked very good, and the less efficient the engine design (read indirect injection) the better the results should be.
BTW it will actually REDUCE the exhaust gas temps which are caused by unburnt fuels and this system purely promotes better burning.
Unfortunately I came across a Snag with mine when i went to actually see them and book it in. I can't fit a big enough tank underneath to suit my 150L main because of the control arm length and location. The biggest they could get in was 18L useable, and at 30% consumption that aint great. It was going to cost closer to $5500 pre-rebate to add a 2nd tank,plumbing and exhaust reroute :(
So the idea got shelved
I think I'm better off spending 2K on new pump and injectors as she's only used for touring and the odd weekend run or camp.
I had a look at a couple of their dyno sheets for the 4M40 and it did look quite nice though.
Rob.
Posted: Wed Jul 23, 2008 9:29 pm
by NJV6
4runna wrote:
BTW it will actually REDUCE the exhaust gas temps which are caused by unburnt fuels and this system purely promotes better burning.
Figures and references Please.
Posted: Thu Jul 24, 2008 6:01 pm
by 4runna
NJV6 wrote: Figures and references Please.
Of?
Posted: Thu Jul 24, 2008 6:20 pm
by NJV6
Lowered EGR's from LPG injection.
I'd like to know more about it but not from the dieselgas or whoever's website as that is usually very biased.
Posted: Thu Jul 24, 2008 6:57 pm
by 4runna
Ah gotcha,
really just design basics I suppose, I'm just going back to the tafe days knowledge.
The main problem with diesels is poor combustion, they are a very cool running engine and therefore designed around that. A common problem that occurs is people try to wring the last little bit of power out of them by adjusting pumps etc which might lead to a fraction more power from increasing the fuel delivery but put exhaust gas temps through the roof, because when it then is released from the chamber the unburnt hydrocarbons continue to burn. Just look at the toyota surf forum, there is constant chatter about doing this, especially on the 2.4s but they are usually talked out of it by other members for this reason alone.
From personal experience, I have worked on them after people have adjusted their pump for more power, and the damage can be catastrophic which it sounds like you already know.
So, back on topic, if the injection of another catalyst improves burn efficiency (which seems to be the case going by design and results) then the exhaust temps should be reduced by better engine efficiency as it's burning the same amount of fuel more completely.
You can actually get a similar thing with petrol motors, but the amount has to be tiny (like a leaking diaphragm in the convertor)
I suppose Ethanol blends are similar, ethanol has more molecules of oxygen right? so by itself it is less effieient as there is less combusitble material, but if you use a light blend like E10 it can actually increase the burn efficiency as it's adding more oxygen (like forced induction)
Sorry that's a waffle isn't it? as I said, going by old knowedge when I used to work on cars, I haven't seen one on a dyno with exhaust gas temp sensor. And it's not by their design, it's just a positive symptom of the system....well should be in theory.
Rob
And the disclaimer.... In My Humble Opinion
Posted: Thu Jul 24, 2008 8:16 pm
by -Scott-
4runna wrote:I suppose Ethanol blends are similar, ethanol has more molecules of oxygen right?
Interesting question. You've got me thinking, now. (It hurts.
)
4runna wrote:so by itself it is less effieient as there is less combusitble material, but if you use a light blend like E10 it can actually increase the burn efficiency as it's adding more oxygen (like forced induction)
Ethanol only has one oxygen atom per molecule, but I think that's a bucket-load more than benzene (is that the common constituent of petrol?)
However, AFAIK, ethanol has only one "unsaturated" (can't think of the right term) chemical bond, where a benzene ring has three - which is (I thought) where the chemical reaction of combustion actually begins.
So, now I suspect I've got it all completely wrong (again
), so I'd love to know if anybody here really
knows how ethanol helps the combustion process...
Posted: Wed Jul 30, 2008 11:40 pm
by Sammyboy
I know that I am a bit late to join this discussion, but if you are still reading it, I may have some info that could be useful
... Last year around this time, I took my car to a specialist who upgraded my fuel pump, and increased my turbo boost (from 8 to about 12psi I think) and told me to fit a 2.5" exhaust system (I fitted this exhaust system prior to this work being done). I was a bit reluctant about this at first ($420 for exhaust, $400 for fuel pump repairs and $890 for fuel pump upgrade) because I am a bit obsessed about my fuel economy (I had new injectors fitted in 2005) and I didn't want my fuel economy to reduce in any way at all. As it turned out, it is the best thing that I could possibly do to the car. It has about 25% more power which is 60kw at the wheels vs 45kw, and 591nm of torque (as printed on my dyno sheet- that's more talk than an Aston Martin V12 Vanquish!
) vs about 340nm. I just got back from my first major trip since the upgrade, and my car hasn't missed a beat. I got 10.5 L/100km towing a loaded trailer through crosswinds, 10.5 over the rough stuff (mostly 2WD with a little bit of 4WD use) and I got 8.9 for easy highway driving, and my worst figure on this trip was 11.8! This is all with my 1990 NG 2.5TDI Paj fully loaded with luggage and equipment, and with two adults and a kid! I reckon those figures are pretty impressive