I wanted to make a dedicated thread and finding out what people extra fuel consumption in there dual fuel EF/EL & AU, so if u have a Impco, Airod or Landi renzo system or other mixer ring setup please responcd to this thread but only if ur information is spot on.

I currently get 400kms per 65L petrol and 330kms per 65L LPG and the formula to work out extra lpg consumtption as follows

Special thanks to JC for the formula

65/400*100 = 16.25l/100km
65/330*100 = 19.7l/100km

(19.7 - 16.25) = 3.45

3.45/16.25 *100 = 21.2% increase over petrol consumption

Now I have taken my petrol tank a tad under quarter tank so where the red section is to get my 400kms out of petrol and I have taken my lpg till when it starts to cough when it dosent have enough gas to support higher rpm driving to get 330kms.

If you all can do the same or super close then that’s great as then we can all be on he same page.

Please keep to this layout for ease of use and reading and here is mine to start of with

Ford Falcon EF XR6 sedan
144,789kms automatic transmission

Petrol usuage 400 kms per 65L
LPG usuage 330 kms per 65L

65/400*100 = 16.25l/100km
65/330*100 = 19.7l/100km

(19.7 - 16.25) = 3.45

3.45/16.25 *100 = 21.2% increase over petrol consumption

85% city driving and 15% highway driving

Also if u have any recommendations to getting better consumption figures then please share this info or found that using a certain oil or spark plug and what not helped with consumption.

Cheers

Lets keep this thread clean please

I have used Autolite XP63 with new perfomance NGK ignition leads done the trick.

AU with a landi converter and simple mixer with a Gastec fp32.

320km to 50L of LPG city driving.

tickford_6

Thats very good economy

yea i'm a nut for it though, I will spend hours trying to perfect things.

Some times it will get as bad as 300km to 55l but it also get a little better

Man u need to come and tune my car lol

I believe i have a Gastec processor but have always thought i can get more out of it.............

which gastec is it?

Getting more out of mine meant disconnecting the gastec and using the stepper as a power valve.
then using a wide band sensor in the tail pipe, adjusting the converter until it's just on the rich side across the range, then connect the gastec again.

Being my own car I don't mind spending all weekend with my wife driving while I watch the wide band.
It's a little off right now though, we only 305km to 50L last week. And it's a little rough coming off idle, But i havn't touched it for over 6 months


One thing the falcons have an issue with is the earth for the ECU. If you have a multimeter and wiring diagram you can check the voltage drop from the bettery to the ECU on the earth wire.
It also important the O2 sensor is working properly.

What size mixer is fitted?
what converter?

Impco 200 mixer and LPG spares B2 style converter

I'll find out which model gastec it is and get back 2 u

I just read through your post again. %21 is pretty good for what what you have
By the title of the post i thought you had a simple mixer system, not an impco system.


Your consumption as a whole is pretty crappy. I would suspect you have some issues that need sorting. As its bad on both petrol and LPG, look at things like spark output, compression, blockage in the exhaust, any sensors that may effect ignition timing ect. and driving style.


As you have probably seen in other posts, I don't like over thick oil. 15w40 or 10w40 is what you should be using, even if it burn a little, so long as it stays on the dipstick over 5000km i would keep using the Xw40,

Do a full transmission flush and use Fuchs synthetic fluid, Titan ATF4400, a full flush will need 20L
You could try a full syn engine oil like fuchs titan supersyn 5w40, but i doubt you'll see any difference over the semi syn GTO 10w40.

As for plugs i've used everthing from regapped stock plugs then bought plug that come with the smaller gap, the autolite the JMM use (autolite 985) again i doubt you'll notice a difference.
Just use Denso W16EXRU, they come with a 0.8mm gap that will suit the LPG using the EF coilpack.

I've been told it should get about 50kms more on petrol and abit more on lpg but as i do alot of stop and start, turning off and on like 10 times a day contributes to higher consumption.

I do have a slight miss and comp is very good but do have a couple leaks in exhuast and empty cat as it rattles at certain rpm. I have replaced 02 sensor but havent looked at others, any suggestions of other to look at???

Have done a full trans flush 3000kms ago and service it every 20,000kms. I also do a engine oil every 3 months regardless of kms with Cooper or Genuine Ford filter. Note i do between 1000-1200kms per month

Have used Denso W16EXR-U and now have Bosch WR8LC+ 0.7 gap but also going to try WR8DC+ 0.9 gap and maybe WR9LC 0.8 gap

Done abit of spark plug research and it was said that if the plug is more in the combustion camber it will burn better and get better performance/economy.

This is what i found from measuring from thread to tip

Denso W16EXR-U 24mm
Bosch WR8DC+ 27mm
Bosch WR8LC+ 25mm

Most carby style LPG systems are very easy to tune yourself. A wideband is a very useful tool in the pursuit of both power and economy!

On my EF before I supercharged it, I used to get 15.5L/100km on LPG combined cycle or 12.3L/100km on the highway. This is with a hi-stall, Wade 1521a, headwork/headers/exhaust.

The right spark map is very important in getting the best out of an LPG setup.

Jason

ignition is super important and have considered getting the E-Gas ignition map on a chip but abit concerned about having issues, as its my daily driver and carnt afford to be stuffing around with it.

Hi all
I have a AU2 ute that has a sprint gas systerm in it. Paccie headers 2.5 cat and systerm right through. I travel from Lake Munmorah on the central coast to near Kurri Kurri (inland from Newcastle) for work. Its around 65km each way. I get about 400km to a tank on average. My tank is 65Ltrs with around 60Ltrs usable. This is a lot of quiet 80-90km/h roads and around 25kms of hiway each way. When im of on a big drive for hols down the freeway i get around 500-550km to 60ltrs of gas. The gas systerm needs a good tune as i have fixed the exhaust since the last tune(8 bends removed from a meter of straight pipe past the gas tank made a big diference to preformance). Just waiting to finish my 3in intake and find some cash for a new BIG mouthed snorkel before another tune.

If anyone can point me in the way of a good gas mech on the coast from gosford to newy would greatly apprecate

If your cat rattles Mickyyy, it's collapsed and blocked, not empty. This will bugger both performance and economy due to excessive back pressure. Replace the cat, it'll be one of the best bang for buck "mods" you ever do.

"65/400*100 = 16.25l/100km
65/330*100 = 19.7l/100km

(19.7 - 16.25) = 3.45

3.45/16.25 *100 = 21.2% increase over petrol consumption"

Can i suggest a quicker way to get figures:

65 / 400 x 100 = 16.25 per hundred
65 / 330 x 100 = 19.7 per hundred

19.7 / 16.25 x 100 = 121% increase.

But i just now see how the other way is a better way to perform calculations.
The variance figure is dividable from individual figures to give easier differentiation.
(Does that make sense) - Well i failed Statistics at uni