Soldato
17000 miles a year is a heck of a commute!
Out of interest, what's the real world mpg you're seeing from the 370Z on motorway journeys?
Out of interest, what's the real world mpg you're seeing from the 370Z on motorway journeys?
Is it crazy to buy a diesel now?
- Thread starter kaptainmarc
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Soldato
Fair enough!
I've done 15k this year but a good chunk of that was paid for with expenses!
I've done 15k this year but a good chunk of that was paid for with expenses!
its not too bad as its an easy drive with fairly quiet roads.
I'm averaging around 25-26 mpg If i drive at 60mph on cruise control I can get 30+, one short blast though and all thats ruined. Defeats the point in having the car for me.
with a heavy foot its low teens.
I drove to devon from derby at 11pm so no traffic cruising at 60-65 and the trip was reading 36mpg that was the most boring drive I've ever had.
17000 would be living the dream for me, currently it's around 25000
In an old job i was doing 25000 services came round real quick! did that in a 2005 suzuki swift sport. not the most comfortable commuter but I was younger then.
Soldato
Agreed. The 370Z is a car meant for enjoying. Gunning for top fuel economy in it is just such a shame!
Soldato
Yeah I don't disagree with that. For me it'd be a case of "can my fuel money be covered by expenses when babying it for work". Having car allowance means I get rubbish mileage expenses up front, but can claim the difference back later on. But if you can't claim any of the mileage back then may as well get the maximum mpg car that OP can enjoy and then enjoy that S2000 mentioned at weekend.
Associate
I can average around 40-45mpg in my Focus ST diesel. If its purely motorways and A roads, on cruise i can hit high 50's but its the town driving/traffic which destroys it 
Modern DPFs are a lot more reliable than they used to. The E9x range of BMWs constantly had issues for example, there's no such issue in the F3x range as they've introduced passive regeneration.
A speed awareness course kind of woke me up to this, dropping 10mph to 70 will likely increase fuel economy, and cost you a whole 3 minutes per day extra. Unless you're doing significantly over the limit, there's just not much point over commuting distances.
Associate
Exactly this, why risk speeding when it literally saves you minutes. On a 100 mile journey you will only save 10 minutes if you traveled at 80mph rather than 70.
But we now have "smart" motorways with their randomly generated speed limits to catch people out 
Everyone has put their foot down for fun though. Who hasn't vmaxed a car on an empty motorway? If only to see how scary it is and never do it again
Everyone has put their foot down for fun though. Who hasn't vmaxed a car on an empty motorway? If only to see how scary it is and never do it again
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Soldato
Going at 80 on the clock is more like 75 anyway
Highly car specific, some are way better than others, my TT seems to overread by 1mph in any scenario from what I can tell. Its definately far far closer than 5mph out.
My mini seemed to be out by around 1-2mph until around 40, then 2-3 up to "commuting" speeds.
Easiest way stick your car on cruise, drive past a decent load of markers (like 10 so you do 5km) on a motorway (500m markers) and then calculate the speed. Get a mate to time it obviously so its within a couple of seconds.
Soldato
They will certainly have a little slack in, they are not allowed by law to under read.
What you say about wheel size is probably partly it, although not the size of the wheel, but the rolling circumference of the tyre, as they will vary across the range.
Autoexpress did one earlier this year, 10 cars at 30,50,60,70
30, range 27-30
50, range 47-49
60, range 57-60
70, range 67-69
The good and the bad were consistent, kia always 3 under
Volvo 30,49,59,69, nears as damnit on spec. There is certainly nothing that would indicate the volvo is likely to be doing 75 when indicating 80, probably 78 or 79
They all I think stayed within 1mph at all speeds of accuracy, so if they were 3mph at 30, they were 2 or 3 out across the speeds.
https://www.autoexpress.co.uk/car-n...erances-revealed-is-your-cars-speedo-accurate
Caporegime
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- 21 Jun 2006
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what about a 450 mile journey?
You arrive later, but plus side is you dont have to pop up on the forum asking 'I was flashed will I get a ticket' as we see occasionally
Soldato
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I've done over 45k miles a year some years but eased off now - I'd rather stay away if the commute is too long.17000 would be living the dream for me, currently it's around 25000
Personally, I don't want a diesel again. Modern petrol engine are pretty good now, catching up with diesels somewhat. A downside with a diesel is that when it goes wrong it can be more expensive to repair so you can easily (if unlucky) give back money saved on fuel.
A normally aspirated efficient petrol engine would be good if covering plenty of miles. Modern turbo'd engines are good for economy too but could suffer a similar expense to a diesel engine if the turbo blows.
If I did buy a diesel again it'd have to be an auto too. The narrow power/torque band ca be annoying. With all the bad press now on diesels, I can't help but think it would be a bad decision
Yep a lot of people don't realise this.
Also that's going on the presumption that the 100mile journey will be congestion free. I've seen it a number of times where cars have flown past me doing god knows what speeds, and 10 miles down the motorway where there's congestion i bump into them again. So they've hit the congestion before i have, but they've not managed to make any further progression, and will have consumed considerably more fuel.
Soldato
Happens to me all the time when using the French autoroutes to/from Toulouse airport. Car blows past doing at least 150kph only for me to catch up to the car at the next Péage 20 minutes later. Doubly amusing when it’s just the driver in a Brit RHD and they have to shimmy over inside the car to pay.
Soldato
Yep so as others are effectively saying, the key is not just the speed (or attempted speed) but also the traffic.
11pm-5am unless there are roadworks if you setout to drive at 90 you would probably pretty much manage.
6am-11pm on most roads I know much harder and during rush hours, not a chance, you will end up with shorter sprints and longer periods of being held up the faster you try to drive.
11pm-5am unless there are roadworks if you setout to drive at 90 you would probably pretty much manage.
6am-11pm on most roads I know much harder and during rush hours, not a chance, you will end up with shorter sprints and longer periods of being held up the faster you try to drive.