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does anyone know if the S4 can be modded to run on gas - it would make alot of sense for the mundane days when performance is not required or is it not possible on a turbo motor

If you mean LPG, I don't think you can convert turbo cars [img]images/graemlins/crazy.gif[/img]

Most definitely NOT!

It is possible but there is a sufficient amount of electrical control over it i dont think.

Call my dad.

Shropshire Auto Gas

01939 260702

He is LPGA registered and will be able to give you some decent advice.

Greg

The August edition of Audi driver has an article on a LPG converted 2.7 twin turbo V6 All road.

Work was performed by some Swiss company I think and presented at the Geniva motor show. I don't have the Mag here at work.

So yes it is possible but I'd be very carefull who you approach to do such a job. A colleague has had an intermittent miss with his conversion on a Civic. Having spent £2K on the conversion he's rather pissed off to say the least cos Like so many things the guys who do the conversions only know how to fit the kit, they don't know the specifics of the engine management etc. So they're after sales service has been far from satisfactory.

But I too thought about those long journeys on the motorway hhmm..

Well I stand corrected.

So what sort of torque/power does an LPG 2.7 biturbo give? I assume it will be well down on the petrol version?

The power and torque were down about 17% I think, however the explanation was that the gas actually has a higher octane rating than petrol, it just doesn't perform well in low compression engines (which unfortunately most turbo cars are)
It did say that in high compression engines you could expect almost identical figures to that of petrol.

....but where would I put my millers? (don't answer that [img]images/graemlins/grin.gif[/img] )

Someone I know has converted a range rover and reckons it is a lot smoother and quieter.

From talking to him my understanding is that most conversions still retain a petrol tank (sometimes reduced in size though), so if you run out of gas or cannot find a garage that sells it you aren't totally in the sh!t.

Since you can freely switch between the two, it could be that you simply switch to petrol when you need the extra welly, then back to gas for the Motorway slog [img]images/graemlins/tongue.gif[/img]

Oh, and you then would still have somewhere to put your millers too [img]images/graemlins/nodder.gif[/img]

Since you can freely switch between the two, it could be that you simply switch to petrol when you need the extra welly, then back to gas for the Motorway slog

Except because there would be some of the LPG still left in the fuel pipe before the petrol reached the injectors, you would have even worse lag than a WRX....or an RS4 [img]images/graemlins/flamethrower.gif[/img]

lol [img]images/graemlins/smirk.gif[/img]

I have no direct knowledge of these systems, but was under the impression it was a seamless switchover (unless you ran out of gas/petrol before the switchover of course [img]images/graemlins/grin.gif[/img] )

turbo lag, what turbo lag ?
I haven't got on boost yet ! [img]images/graemlins/roflmao.gif[/img]

range rovers are well suited to LPG conversions because a decent system has been developed. what lets alot of them down is that there control systems are no where near as sophisticated as the stock ECU's and there isnt as much control, adjustment and safety built in.

You've nailed it on the head. I'm sure that's exactly what the Audi Driver article said. Which is no supprise when you consider the 2.7 V6 30V variable valve timing which works on the principle of two separate banks of 3 will take a lot of ECU work - beast! [img]images/graemlins/colours.gif[/img]