Performance after converting to LPG

[Gruff!]

I was just thinking out loud, but would the "performance" ie 0-50 time etc alter once you convereted a 1.9 petrol over to lpg?

I can see the cost of the fuel goes down but how about the miles out of a full tank, on average do these increase, and does lpg make the van run smoother/faster or is it much the same as using straight petrol?

Thanks
Gruff!

[wookey]

lpg has 80-85% calorific value of petrol . so its logical that you get 80-85% of your performance on LPG. However if its like my lpg golf the 0-60 times were load dependant. I.e. they were the same with just me in add 4 people in the car thats when you noticed you only had 85% of the performance. Running on lpg you will see your mpg drop but 15-20% obviously this is not too bad as you offset that against the cost of gas. My rule of thumb was you save about 40% over petrol running on lpg.

However I did program my romano system to add petrol above 4500 rpm. this gave me back the full perf of petrol. was a life saver when u needed that little more to overtake etc normal crusing never went over 4200 so was on lpg normally

[mike_gee32]

Depends on what condition your carb is in and what you do with the power valve. Mine which was converted a few years ago by Steve at Gassure only ever did about 22mpg max on petrol, it would sit happily at an indicated 75ish on the motorway (at about 18mpg) On gas, after spending quite a long time tweaking the power valve, I'd regularly see 24-25mpg and there didn't seem to be much difference how I drove it, 200miles at 70+ on the M1 and it would still do 24mpg. Acceleration was a little slower but if anything it seemed happier to sit at high revs, it would happily cruise at an indicated 80mph with a very light right foot. By winding the valve out a 1/4 turn it would accelerate much better but didn't like high speeds as much (and took the mpg down to petrol levels) - I think this is the biggest limitation of the simple open loop system used on most carb'd cars, you can only really set the gas flow for one set of revs/load.

When we would go to Cornwall I'd cruise down with the valve in, when we came off the motorway I'd wind it out a bit so we had some power for the hills, then reset before going home.
You can't really compare the system on a 1.9 to a modern injection system, the WBX engine seems to love LPG.

Get it done!

[Mocki]

my 2.1 is set so i have as much (infact maybe a little more) power on lpg than on per-petrol, and the mpg is as far as i can tell the same, 19-26mpg depending on type of useage. I do plenty of towing and load lugging , its my only vehicle so gets used for everything.
its a 2.1 DJ running a DG carb and manifold.

keep it below 70mph and its economical, accidentally slip over the 70mark and it drinks it abit...... but then it does exactly the same on per-per-petrol.

flat fours love lpg. smoother, cheaper, and your putting less into gordys pocket.which is the most important bit

[scottbott]

'programme my romano system' what does that mean?,dont have lpg just curious

[wookey]

hook a laptop to the lpg ecu (made by romano) and tweek all its settings.

[toomanytoys]

"romano" is a manufacturer of LPG systems..
On injected systems (and some carb ones) its poss to programme different asspects of the fueling..

I have run LPG on a T25's for a long time.. (converted my own and wrote the LPG feature in VW camper and commercial mag quite a few years ago too..) and to be fair.. a properly set up system will perform as good as when on petrol and if any loss is there, its barely noticable...

[kevtherev]

I have a 2.1 on gas with a carb, not injection.
No issues with power, there's a trade off with LPG and it's smoothness against the petrol lumpy shaky.
I have 24 mpg on gas with guts for hills.

There are so many more gas stations these days, and in Europe, especially france, it's better than here

[ghost123uk]

I am totally happy with my (Gasure) LPG system.

It is easy to adjust the mixture valve to get either max power or max economy ( I have mine set half way between the extremes !)

1.9 DG = around 22 on a run out (and I don't pussy foot, though I don't thrash either)

Performance, the way I have it set, it is indistinguishable from petrol.

Running = mine runs much smoother on LPG (though that could be because my carb might need a "looking at" but as I hardly ever use petrol in can stay like that for now !)

[lloyd]

Running = mine runs much smoother on LPG (though that could be because my carb might need a "looking at" but as I hardly ever use petrol in can stay like that for now !)

I feel that after conversion carb engines don't run as well on petrol as before. Reason? Because the gas noosle/tube (12mm-ish OD) is in middle of carb to restricting/changing airflow in carb... which causes carb to perform different then it should. These tubes also restrict total airfow to carb.

That said, I am more then willing to live with gas conversion as the savings far outweigh these changes.

[Rafa77]

What`s the average LPG conversion cost? Im running a 2.0 litre Aircooled at mo and he likes the taste of petrol, admittedly issue with carb at moment (see wanted post).

[lloyd]

£1000+

[kevtherev]

from gasure

Air-cooled single carb £899.00 + vat and twin carb £975.00 + vat fitted complete