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What sort of average fuel consumption can I expect from a 3.2 Q4 Brera, currently I seem to be struggling to get more than 22 MPG as opposed to the 28 - 29 I used to get from my Peugeot 406 coupe 3.0 litre?
Has anyone here converted to LPG and if so what effect has it had on performance and costs per mile?

Regards
Roger
 

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the Q4 transmission saps a lot of power/fuel + the Brera is probably heavier and less aerodynamic than the 406 C

I queried a couple of LPG conversion outfits about doing the V6, but both said they couldn't do it due to the direct injection system. I'm sure it can be done though as kits are readily available for the 2.2 which has a similar injection system
 

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Going light on the throttle with few gear changes (eg long motorway runs) should see it go above 25mpg.
My SWQ4 does and so does Simon's Brera Q4. When I can be bothered to do tank full to tank full checks (ie over a variety of roads on both long and short journeys) it is averaging somewhere 22 to 25mpg.
 

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Jumping Jesus, I thought 31 mpg from my 2.2 159 was bad :wow:
 

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Jumping Jesus, I thought 31 mpg from my 2.2 159 was bad :wow:
31 ain't bad in the 2.2, I'm getting under 30 unless I drive like a granny :eek:.
 

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By sticking to 100 km/h I've been able to squeeze 700 km out of a tank of 98 octane. Those were undulating roads, with little time spent in small NSW towns. I think that one took about 70.5 litres. The nominal capacity is 69 but there's another three in there somewhere. Just driving around Canberra mine has dropped to 15 litres per 100 km, still on 98.
 

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22mpg is about right for the Q4 V6.
My 159 being a qtronic (6spd auto) is worse still sometimes averaging 16mpg around town.
For the same reason I've been looking into LPG conversion & have found a company called Mint LPG who will convert the direct injection JTS using a sequential Romano N system for around £1100.
It's very tempting as it works out the equivalent economy as a JTDM in terms of running cost.
 

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22mpg is about right for the Q4 V6.
My 159 being a qtronic (6spd auto) is worse still sometimes averaging 16mpg around town.
For the same reason I've been looking into LPG conversion & have found a company called Mint LPG who will convert the direct injection JTS using a sequential Romano N system for around £1100.
It's very tempting as it works out the equivalent economy as a JTDM in terms of running cost.
It isn't something I'm considering, but out of interest where are they proposing to put the LPG cylinder?
 

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Yeh, tank in the spare wheel well.
Obviously will have to loose the spare wheel & jack & switch to tyre foam sealant.
Most new cars are using this now & done away with the spare.
 

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I had a 4.4 range rover with lpg and it was a complete nightmare.

The filters kept getting clogged up and it would revert to petrol (apparently LPG is not particularly clean and clogs filters quickly), the tank was only 90 litres but I could only get 80 litres in it so after 100 miles or so I was looking for another fuel station that sells LPG and there aren't all that many around. Driving to Cornwall I had to fill up twice just on the way down and had to plan my journey in advance around LPG locations.

When you do find an LPG station, there is generally only one lpg pump and you usually have to queue for it. And, LPG has a different calorific value to petrol so you use about 10% more lpg compared to petrol.

So in short, it is cheaper to run a car on LPG than petrol but there are drawbacks. I got rid of the thing after 7 months and went back to diesel, slightly higher running costs to lpg but with a 600 mile range.

Rant over!:thumbs:
 

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I have averaged 24.5 mpg over the past 2000 miles in my 2.2 Brera so I would say you are doing very well in the 3.2 unless that is all steady motorway driving.
 

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I had a 4.4 range rover with lpg and it was a complete nightmare.

The filters kept getting clogged up and it would revert to petrol (apparently LPG is not particularly clean and clogs filters quickly), the tank was only 90 litres but I could only get 80 litres in it so after 100 miles or so I was looking for another fuel station that sells LPG and there aren't all that many around. Driving to Cornwall I had to fill up twice just on the way down and had to plan my journey in advance around LPG locations.

When you do find an LPG station, there is generally only one lpg pump and you usually have to queue for it. And, LPG has a different calorific value to petrol so you use about 10% more lpg compared to petrol.

So in short, it is cheaper to run a car on LPG than petrol but there are drawbacks. I got rid of the thing after 7 months and went back to diesel, slightly higher running costs to lpg but with a 600 mile range.

Rant over!:thumbs:

Doesn't sound too good reading your experience with it.
I expect LPG to be harder to get & the economy to be slightly worse than when running on petrol but 100 miles on a full tank of gas is shocking even for a 4.4.
I get just under 300 out of a tank of petrol so would expect 260ish on gas if it's 10% less.
Need to look into this.
 

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You'll never get the same mileage per tank due to the size of the tank, and LPG being only about 80% as efficient as petrol.

I once had a Discovery 3.9 Rover V8 on gas and it was OK because it had twin torpedo tanks under the car to give added range. My only problem was when flooring it, it used to switch back to petrol too readily for my liking. It also used to splutter on really cold days when flicking over to LPG in the morning.

I'm pretty sure I wouldn't pay out to convert a car to gas myself, I can't see the benefit myself :confused:
 

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From the research I did when thinking about getting a V6, the systems fitted to newer DI engines are more efficient than the ones fitted to older engines and can be run on LPG from a cold start
 
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