Fuel Consumption at 85-90MPH

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Thu 7 Jul 2016 14:49
Fuel Consumption at 85-90MPH - pitbull
Hi all,

I drive long distances daily on the motorway at about 85-90MPH. I cover about 35k per year. I currently drive a 2008 VW passat 2.0TDI. Costs about £70-£75 to fill up and I achieve about 600 miles.

Looking at official mpg figures I could get a similar sized car with greatly improved mpg. Do you think these figures would show similar % improvements to what I am currently achieving when travelling at 90MPH?
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Thu 7 Jul 2016 15:38
Fuel Consumption at 85-90MPH - RT

Euro 6 cars mostly show an improvement in official figures over the Euro 5 counterpart - but in reality have worse consumption - look at HJ's Real MPG for comparative figures.

No-one driving at 85-90 gives a s*** about fuel consumption - if they did, they'd drive within the speed limit - that's your easiest, cheapest way to improve your fuel consumption.

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Thu 7 Jul 2016 16:07
Fuel Consumption at 85-90MPH - gordonbennet

Yes, most vehicles once you get past the legal limit you are shifting masses of air and consumption plummets.

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Thu 7 Jul 2016 17:20
Fuel Consumption at 85-90MPH - mss1tw

Yes, most vehicles once you get past the legal limit you are shifting masses of air and consumption plummets.

I just drove to Dorset and back and got 10mpg more by simply sticking to 60mph and behind trucks MOST of the time. I filled up before and afterwards and as usual logged the data on my phone so this is a verifiable improvement.

There were occasional forays into the sort of speeds the OP mentions.

I'm only human, after all. ;)

The main economy killer for me is town driving.

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Thu 7 Jul 2016 16:20
Fuel Consumption at 85-90MPH - chriswales

No-one driving at 85-90 gives a s*** about fuel consumption - if they did, they'd drive within the speed limit - that's your easiest, cheapest way to improve your fuel consumption.

Very true, I do a 70 mile daily commute which is mainly motorway. I have a target spend of 75mph depending on traffic and I’m constantly passed by cars doing over 80mph with blue motion/tech or eco written on the back.

Interestingly I normally see they’re the more fuel efficient models once I’ve caught them up in the queue to exit the motorway. Does make me wonder why people bother paying extra for such cars then drive them in such a way. They’d be better off in the standard version of the car.

Edited by chriswales on 07/07/2016 at 16:23

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Thu 7 Jul 2016 17:09
Fuel Consumption at 85-90MPH - RobJP

No-one driving at 85-90 gives a s*** about fuel consumption - if they did, they'd drive within the speed limit - that's your easiest, cheapest way to improve your fuel consumption.

Very true, I do a 70 mile daily commute which is mainly motorway. I have a target spend of 75mph depending on traffic and I’m constantly passed by cars doing over 80mph with blue motion/tech or eco written on the back.

Interestingly I normally see they’re the more fuel efficient models once I’ve caught them up in the queue to exit the motorway. Does make me wonder why people bother paying extra for such cars then drive them in such a way. They’d be better off in the standard version of the car.

Ahh. The answer is simple.

Company car tax. Because it is the eco version, C02 is lower, so the % BIK is lower, meaning the car is cheaper for the rep / lower management who drive them.

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Thu 7 Jul 2016 19:49
Fuel Consumption at 85-90MPH - chriswales

If that is the case then it’s rather disheartening that a scheme to help improve things is being used by people to save money without achieving the intended goal.

I guess there could be a trickle down benefit when those cars are sold on, but newer cars do seem to have a higher failure rate of components.

That is of course rather a mute point, since under normal operating conditions the cars don’t actually match the advertised CO2 and fuel consumption figures.

Edited by chriswales on 07/07/2016 at 19:50

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Thu 7 Jul 2016 19:25
Fuel Consumption at 85-90MPH - craig-pd130
Hi all, I drive long distances daily on the motorway at about 85-90MPH. I cover about 35k per year. I currently drive a 2008 VW passat 2.0TDI. Costs about £70-£75 to fill up and I achieve about 600 miles.

What is your actual miles per gallon calculated at the pump?

I usually cruise on motorways at 80 / 85 indicated. Thinking about the cars I've owned, my 2003 Passat PD130 used to give a genuine 50 - 52mpg at the pumps on long motorway journeys.

Same with my previous Volvo V60 D3 and my current V60 D4.

I think it's unlikely you'll ever get much more than a genuine 50mpg from any car if you're cruising at highish speeds.

As others have said, you could make a much bigger saving on fuel by slowing down by 10mph or so, if the cost matters.

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Thu 7 Jul 2016 21:31
Fuel Consumption at 85-90MPH - Smileyman

not sure where you guys drive and get away with 90, I'm guessing it's not the M25!

If there are any German speakers reading this perhaps you could mention whether any tests have been undertaken in Germany driving at (say) 110/130/160 kph (approx 70/80/100mph) with results.

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Thu 7 Jul 2016 23:46
Fuel Consumption at 85-90MPH - galileo

not sure where you guys drive and get away with 90, I'm guessing it's not the M25!

If there are any German speakers reading this perhaps you could mention whether any tests have been undertaken in Germany driving at (say) 110/130/160 kph (approx 70/80/100mph) with results.

Most of the M62 and northern M1 are usually too congested to beat 80mph during the day (in the few bits that don't have 50 mph limits and average speed camera enforcement), especially if you are held up by the daily accident (e.g. this week's 7 hour total closure after a multi vehicle crash and fatality).

Unless you are trained to plod's pursuit qualification (or skill levels of Jason Plato) I would suggest that habitual travelling at 90 mph on roads infested with incompetents who do stupid things may one day lead to grief.

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Fri 8 Jul 2016 00:14
Fuel Consumption at 85-90MPH - daveyK_UK

the honda civic crusing at 85+ can do 60mpg or higher

its a very aerodynamic car and the diesel engine like the petrol engines is fabulous

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Fri 8 Jul 2016 10:15
Fuel Consumption at 85-90MPH - slkfanboy

the honda civic crusing at 85+ can do 60mpg or higher

its a very aerodynamic car and the diesel engine like the petrol engines is fabulous

Well the OP is suggesting he can do around 45mpg, which is around what my old 3L petrol jag could do on the motorway @85. So any well geared desiel motoway cruiser well manage better.

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Fri 8 Jul 2016 22:45
Fuel Consumption at 85-90MPH - drd63

M40 West of A34 is usually pretty free flowing so possible to cruise at 85/90 although not unusual to see traffic flow in outside lane going much faster and usually well behaved.

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Fri 8 Jul 2016 23:59
Fuel Consumption at 85-90MPH - Alby Back
I tend to waft along at the legal limit or near to it nowadays. I used to drive like a scalded witch in my younger days but now I'm happy just to glide along most of the time. It rarely makes much of a difference to journey times, even on a long run when you factor in all the roadworks, average speed cameras, traffic congestion etc. But even if it occasionally does add a few minutes here and there I don't really mind, my car is a nice place to sit in and has an excellent sound system so depending on my mood I'm happy to listen to music I enjoy or a broadcast I'm interested in and let the "others" stress themselves out in lane 3. Good luck to them and their licences.

;-)

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Fri 8 Jul 2016 23:59
Fuel Consumption at 85-90MPH - Smileyman

I woudn't name any roads where it's technically possible to drive at 80-90, apart from it being above the legal limit it might also attract the wrong sort of attention - eg boy racers which would consititute a road safety concern

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Sat 9 Jul 2016 00:12
Fuel Consumption at 85-90MPH - John Boy

Why would you discuss fuel consumption with someone who can't be bothered to do a brim-to-brim calculation?

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