Diesel/LPG conversion on D4D

[zoigzy Lurker Find all posts View Profile Close zoigzy]

Greetings All, this is my first post, so please be gentle.

My GX is due for delivery in a few weeks and I've made a few enquiries around the traps about the diesel LPG setup, regarding expected improvements in economy and power etc. No one has been able to tell me if it's actually worth the big bucks to get it done. All the published dyno graphs are for older (inherently inefficient) diesels, and the benefits are clear for those engines.

Is anyone aware of a D4D that's running LPG, and if so, what improvements they have found? My initial thoughts are that it's probably not worth it, because there's not much room for improvement. Please discuss.

[samo Addicted PP Member Find all posts View Profile Close samo]

he zoigzy hows it going, i cant comment on the d4d, or the old diesel, but my mate is getting it done on a 2.8 td pootrol, will cost $4500, they install a 20ltr tank, run it at 5%, change the exhaust and they say he will get a 40% increase in torque and around 15% in power, and the $2000 rebate is available within 10days after fitment, so you will be out of pocket 2.5g,
$2500 buys a bit of diesel, not much but if you do a lot of kms it might be worth it

[DocK Member Find all posts View Profile Close DocK]

Hi Zoigzy, I weighed up the pros and cons of chip v LPG and went for LPG from new - Toyota weren't too happy about it! Anyway, I had it independantly tested after first set up and the dyno read about 5% increase in power and no change in economy - :cry: . Took it back to the installer and after some fiddling and a replacement converter next dyno 20% increase in power and improved economy by about 10% There really has been a significant increase in torque as well. Would I recommend it - yes, but you may have some fiddling to get it exactly right - persist and it really does pay off.

[lawrance Senior Member Find all posts View Profile Close lawrance]

Re: Diesel/LPG conversion on D4D

So does Toyota simply void the warranty of the engine and the entire driveline due to this modification?

:?:

[LiveFreeAndRoam Avid PP Poster! Find all posts View Profile Close LiveFreeAndRoam]

Re: Diesel/LPG conversion on D4D

Hi Dock,

Curiously, as the engine wears in and things loosen up, are you expecting to need to retune this to maintain your improvements in power and economy?

Also, since it was new, what was the baseline you used to compare it with? I guess it was Toyota's spec sheet?

LFaR.

[DocK Member Find all posts View Profile Close DocK]

Re: Diesel/LPG conversion on D4D

The baseline was on the dyno with the gas off. There is dash mounted switch to do this, I also drove about 20km off gas to ensure that no contamination. Dyno done. Gas on - dyno repeated. Did this on both occasions - so I feel that the dyno gave a fair representation of the performance gains specific to this engine. Does Toyota void the warranty - well no actually. The Trade Practices Act ensures that the manufacturer has to prove the modification caused the problem - it would be an interesting debate :!: The current spate of injector problems is so widespread that Toyota would have great difficulty blaming it on the LPG. Anyway the LPG installer put me on to a company that insures the engine against LPG damage - $100 for 3 years. Good value I think. So I took out an additional insurance policy just in case. My view was that Toyota would look at chips that actually change engine parameters much more seriously and it would be almost impossible to argue against a chip that alters timing, rail pressures, and so on. So for me LPG was a safe and yet effective upgrade.

[Hornet Junior Member Find all posts View Profile Close Hornet]

Re: Diesel/LPG conversion on D4D

Hi Dock,
Just curious, if there is a 20% gain in power, wouldn't you want to look in upgrading some of the drivetrain components as well?
Like diffs, gear box, etc. Surely, adding 20% of power puts the same 20% extra on components that were designed and built originally for, say a 100% of power.
Now, after this mod, the same parts experience 120% of design power applied meaning extra wear and tear. Diffs are known for their weakness in Prado as they are.
Toyota may have a good case against you if things go wrong and you want to make a claim.
Just my thought...

[DocK Member Find all posts View Profile Close DocK]

Re: Diesel/LPG conversion on D4D

Thought about that one quite a bit at the time. Couple of points; my understanding was the 5 speed auto was also found in the 120 series petrol (170KW) also, I think, in the 100 series including the petrol engine so that should be strong enough to cope - I hope that is correct. The diffs - well, I was going to replace them sometime with airlockers anyway - should they go it will force the decision - honestly I hope they don't for a while - 4WDs can become an expensive habit . The combination of locked diffs and traction control would be my ideal traction solution - frankly I need all the help I can get :!: Being a conservative type driver, I don't push too hard so I figured that I would not be using maximum torque very often to stress the drivetrain. For example I don't tow much weight just a trailer and kayaks occasionally. I also hope that Toyota has over-engineered things a little to ensure reliability - guess I will find that out. So all up I figured the Prado would take it. Then off course there is that insurance policy on top of the Toyota warranty. All in all I guess it is a balance of risks - I chose risk - time will tell. If the unimaginable happens I will put a very humble post on Pradopoint :roll:

[Duff Junior Member Find all posts View Profile Close Duff]

Re: Diesel/LPG conversion on D4D

Does the tank fit under the car on a 120?

[photoprado Avid PP Poster! Find all posts View Profile Close photoprado]

Re: Diesel/LPG conversion on D4D

my understanding was the 5 speed auto was also found in the 120 series petrol (170KW) also, I think, in the 100 series including the petrol engine so that should be strong enough to cope - I hope that is correct.

Like all engine performance mods, I think the resulting driveline reliability will depend more on how and where the vehicle is driven than the outright durability of the components.

That said, I think you will find that it's the torque that kills the driveline more than the KW. What sort of torque figures did you get from the dyno?

[mjforder Senior Member Find all posts View Profile Close mjforder]

Re: Diesel/LPG conversion on D4D

Hello DocK (and others)

Risk of sounding a little "negative"....I was going to put one of these LPG fumigation kits on my D4D....well, at least until i found out that in all (if not most) states and territories - the installation cannot be certified (due to no emissions testing facilties available for these vehicles) and hence risk being defected by local authorities. In addition, most (if not all) insurance companies will only insure where the vehicle is driven "legally".

Needless to say, i have been involved with my local PM to get some clarification on this (especially as the Feg Gov pays around $2k - thus kinda endorsing the process) and one of the companies.

im keen to get it done. I even was behind a Prado the other week that was LPG equipped. A strange/different exhause smell!

cheers

M

[DocK Member Find all posts View Profile Close DocK]

Re: Diesel/LPG conversion on D4D

Sorry for the delay - forgot my password. I had no problems in SA with legality and insurance. The Fed rebate was also inthe bank account within 2 weeks. It is still going very nicely and runs smoother when the gas is on than with it off. I really appreciate the extra acceleration in overtaking etc. Offroad I dont have to plant the foot as much to get up the dunes. The tank fits where the huge standard muffler fits and a smaller sports muffler is fitted - plenty of room and it is no noisier than standard - at least with the windows up. :!:

[Chuck Advanced Member Find all posts View Profile Close Chuck]

Re: Diesel/LPG conversion on D4D

The tank fits where the huge standard muffler fits and a smaller sports muffler is fitted - plenty of room and it is no noisier than standard - at least with the windows up. :!:

Photo's please.....

[mjforder Senior Member Find all posts View Profile Close mjforder]

Re: Diesel/LPG conversion on D4D

Sorry for the delay - forgot my password. I had no problems in SA with legality and insurance. The Fed rebate was also inthe bank account within 2 weeks. It is still going very nicely and runs smoother when the gas is on than with it off. I really appreciate the extra acceleration in overtaking etc. Offroad I dont have to plant the foot as much to get up the dunes. The tank fits where the huge standard muffler fits and a smaller sports muffler is fitted - plenty of room and it is no noisier than standard - at least with the windows up. :!:

DocK - glad you are happy. I got a letter from the Officer of Senator Hon Kim Carr (Minister for Innovation, Industry, Science and Research) following my letter to Bob Such.....the letter pretty much confirms my post on the legality issue with driving a LPG equipped car in SA (and most other states).

I sincerely hope you dont have problems. That said, im still very keen to get a "certified" kit installed.

regards

Michael

[DocK Member Find all posts View Profile Close DocK]

Re: Diesel/LPG conversion on D4D

Michael, very interesting! Wonder how the diesel/gas supplier/installer gets around this issue in SA where it was installed? Well, I can always switch it off on the road and use it off the road for the extra grunt it provides. Got some photos of the install but cant work out how to post these - sorry.