Thread: diesel gas conversion question

definitely CAN be done....

seems to give useful increases in power & economy if set up correctly

D1 best fitment seems to be 2 smaller tanks, one under each sill

hope this helps

Originally Posted by 87County

D1 best fitment seems to be 2 smaller tanks, one under each sill

If you are doing it to a D1 with a standard size fuel tank, you only need one LPG tank and it will fit under the car. The tank used is 21 litres and 208mm in diameter. Dual tanks will cost a lot more.

I'll let you know in a few hour time - just going to pick mine up after the installation.

Originally Posted by johnd

guys
I've got a 1998 TDI disco which I am considering putting on gas. I'm getting very mixed signals, even from the conversion experts. One school says its great, gives you increased performance and economy and the other says it either can't be done (not enough clearance to put the gas tank under the floor or "never runs right") or not worth doing "no benefit in power or economy" - and these responses from the guys doing the conversion!
I'm quoted around high $3,000 but govt rebate is $2k + $1k (WA).

Has anyone out there done this and what were the pros and cons?

many thanks

johnd

Obviously the ones saying it cant be done either dont know how or dont want the work so they make up excuses rather than tell you the truth.

The truth is that the only real negative I have heard of is that they can do head gaskets but this could be due to some 300s have the normal bonded head gaskets and others have just a steel shim.

The shim will be fine but you may need to change the head gasket if it is the older type.

Other than that, a small 21ltr tank under the drivers side sill is what I have seen and looked neat enough on a standard car and on a body lifted one ive seen it had a 30 odd ltr tank and they only drop down to about 1" higher than the chassis rail.

In vic most places are still asking around $5k that I have asked so still not worth it at the moment.

I picked up my D1 from the D-Gas gas fitter and was instantly impressed. It pulls in 5th gear like it used to in 4th, and runs smoother than before. The dyno graph shows 67.9Kw at the wheels vs 55.2kW without the gas.

I have a 2.5" exhaust, Jase's bigger intercooler, gas flowed head and I had MR Automotive tweak the fuel pump - a bit too much I think as could blow lots of black smoke under hard acceleration and could get the EGT's over 750 if I was not careful. On the way home with the gas on, I could still make a bit of smoke, but it was more of a brown colour and nowhere near as bad.

When I got home I set both the diaphragm and starwheel back a bit to lean it off. I'll test drive it tomorrow and see how it goes.


This is still the first stage of tuning, I have to run it for a few tanks of fuel to work out the ratio of diesel to gas - should be about 20lt of gas to 80lt of diesel. If it's not right I can either go up or down a jet size as necessary.

The 20lt tank is set about 2" below the chassis rail, but it is about 1" below the floor as well. I think I may fit a 50mm body lift and reposition the tank higher to keep the ground clearance the same as before. I will also fabricate a 4 or 5mm steel skid plate to protect the tank etc - it comes with a rather flimsy 1.5mm plate. Apart from the tank, the rest of the installation seems pretty robust - everything is properly tied down with heavy duty clamps and bracket. It cost me $3850 and I'll get back $2000 thanks to Johnny Howard.

The biggest test so far was the steep hill right outside my driveway ( trucks are forever stalling on it and having to reverse down) - before fitting the gas I had to keep it in first gear, as I could not change to second as it would bog down completely, now I accelerate up the hill, change into second and carry on accelerating. :-)

Originally Posted by Iain_B

I picked up my D1 from the D-Gas gas fitter and was instantly impressed. It pulls in 5th gear like it used to in 4th, and runs smoother than before. The dyno graph shows 67.9Kw at the wheels vs 55.2kW without the gas.

I have a 2.5" exhaust, Jase's bigger intercooler, gas flowed head and I had MR Automotive tweak the fuel pump - a bit too much I think as could blow lots of black smoke under hard acceleration and could get the EGT's over 750 if I was not careful. On the way home with the gas on, I could still make a bit of smoke, but it was more of a brown colour and nowhere near as bad.

When I got home I set both the diaphragm and starwheel back a bit to lean it off. I'll test drive it tomorrow and see how it goes.


This is still the first stage of tuning, I have to run it for a few tanks of fuel to work out the ratio of diesel to gas - should be about 20lt of gas to 80lt of diesel. If it's not right I can either go up or down a jet size as necessary.

The 20lt tank is set about 2" below the chassis rail, but it is about 1" below the floor as well. I think I may fit a 50mm body lift and reposition the tank higher to keep the ground clearance the same as before. I will also fabricate a 4 or 5mm steel skid plate to protect the tank etc - it comes with a rather flimsy 1.5mm plate. Apart from the tank, the rest of the installation seems pretty robust - everything is properly tied down with heavy duty clamps and bracket. It cost me $3850 and I'll get back $2000 thanks to Johnny Howard.

The biggest test so far was the steep hill right outside my driveway ( trucks are forever stalling on it and having to reverse down) - before fitting the gas I had to keep it in first gear, as I could not change to second as it would bog down completely, now I accelerate up the hill, change into second and carry on accelerating. :-)

Ian I think Johnd is referring to Diesel-Gas system ,as apposed D-Gas.

They are 2 Different systems.


John , The New Diesel-Gas is a sequential vapour injection system , equiped with an ECU , which monitors the Coolant Temp , EGT , etc and lot of sensors , and it is self adapting to your driving style. you will see a power/torque increase of about 20%.

Iain B,
how many Kms did you have on your disco when Gas was installed and was the motor original or rebuilt.
Do you think it would have performed as well if you didnt have the other Mods and the engine was STD.
As I have looked at this conversion also but thought it might be a waist of time and Money due to age of vehicle. (95 300TDI) and expected engine problems after installation due to Kms on motor already.

Not for "high $3000" he isn't - the Diesel Gas sequential system runs around the $5500 mark