MPG Confusion

[bruce_19]

So I was speaking to some car friends last night and though it rather amusing that yes they know a lot about cars and how to modify them and what helps compliment each upgrade ect ect but when it came to MPG they totally got it wrong.

So talk started as it always did with them talk about 'claimed' figures ect and future plans for the cars then the time came for me to let them know what's happening with my car and I got the normal about driving an auto and it only being a 1.4 turbo. So with my quest to see what works at improving MPG we started to talk about ways of improving it and I realised that people can become confused by it.

What I was trying to get at was if you are doing say a 10 mile trip and only getting 30 mpg because of start stop traffic and your other option was a 20 mile trip but you where constantly moving and get 35 mpg they thought yeah we would always go for the better mpg. The misconception I can see nowadays is that people are so concerned with better mpg and claimed mpg that they are not looking at the real world anymore.

So lets take the 30 mpg 10 mile trip and say get 400 miles out of a tank not the best but not the worst.
Now take the 35mpg 20 mile trip you would get roughly 465 mile out of the same tank which is better isn't it???

Wrong. It may look better on paper but when I comes down to it you are spending just over 1.5 times more in the quest for seeing a better mpg figure than seeing a lower figure but in the long run you are better off doing less miles but being is start stop traffic.

I never really understood the difference till a couple of years ago speaking to my dad about it.

So the quest for a better figure might cost you more in the long run, always look at your options try them out and work out what really is better.

[stigeye]

The flip side of short, stop start journeys is more wear on clutch and gearbox etc. The truth is, it doesn't matter what type of journeys you do, if you can afford to run it and you enjoy driving it, that's all that matters.

[tucpal]

Never really gave mpg any thought at all I just fill up and drive if I was totally eco mined I would go hybrid or eco but I do dislike manufactures unrealistic claimed mpg figures and agree the tests need to be more in the real world

[bruce_19]

Yeah if you can afford it then go for it I done it in my younger days with my Subaru's ect.

My point is we can all be guilty of trying to get to those claimed figures but at what cost.

Gearbox and clutch wear and tear are something people don't think about and if like me you own a car for 3 years then gearbox and clutch don't really get changed in the time you own the car then again it is another factor that can be added in for calculation.

My point is people can be focused on something that they forget other factors that have an effect and if saving money or being more eco is your goal then the mpg figure might not be the best thing to look at.

Take my point for example I took the distance and mpg into account but not the wear and tear of other items which cost to fix.

If we take my example and now factor in a replacement gearbox and clutch supplied and fitted is £1550 so if you have to change it in your lifetime of owning you are still looking at 52 weeks of driving the lesser distance and saving the difference from the longer journey to break even then you are back to saving money.

If your like me and replace parts yourself I have seen a reconditioned gearbox for £750 and clutch for £100 so again going the lesser route has saved money again.

Don't get me wrong drive how you drive take the roads you want too I am just saying there is more to things to think about than what we first look at when looking to save money.

[tucpal]

Agreed don't forget driving a derv about in 5th and low rpm and doing mostly short stop start journeys can ruin the dpf egr etc and if you are going to keep the car for a very long time you must also factor in a dpf replacement as they do have a recommended replacement schedule according to mileage.

[stigeye]

Unless you are very heavy footed, the savings that you make annually by adjusting your driving are minimal. So, if you are heavy footed and were inclined to save money you could save £100+ by changing your driving style. If on the other hand you aren't that heavy footed and just want to go out and drive, and enjoy the experience I would suggest forget about mpg and get on with enjoying the experience as trying to save a treasure trove of money will probably turn out to be a fruitless task.

If saving a few quid a week by changing your driving style is some peoples thing, go for it, but in my experience these things even themselves out in the end, you save on one end and end up paying out on the other. After all, if you were really wanting to save money, you definitely wouldn't join a site like this, where all you end up wanting to do is upgrade everything on the inside and/or outside of your car lol.

[bruce_19]

We are going off the reason for the post.

The main point is people seem to think that driving further and faster getting the car to show better MPG is better than seeing a lower number and taking a shorter route slower (I was one of those people) but it might not be. Like we keep saying other factors have an effect.

There are a lot of posts about MPG and how much we are all getting or not in my case haha this is just to give people food for thought.

I have worked out that if I had a VXR it would cost me an extra £5 a week on fuel or if I got the 2.0 ltr diesel it would save me £4 week doing the route I currently do.

As for upgrades that comes out of a separate fund as the wife thinks car mods are different to maintenance and wear and tear.

[stigeye]

What I'm saying mate is that that the money that can be saved either way is so inconsequential that it's not worth worrying about either way. You can change your driving styles, even change the routes you take, but if you're only saving a few quid a week the money just ends up disappearing down the back of the sofa anyway, you see nothing back from that saving. Hence why I said, unless you are very heavy footed the quest for mpg greatness never really counts to much.

I am sure that if we all drive down a particular road, at a particular speed and [x] rpm in a particular gear we can all achieve a spectacular mpg return, but that's not real life, unless you are doing that route every day and it accounts for the majority of your driving life. So, in conclusion and imho nobody should become engrossed in any kind of debate regarding mpg, driving styles and different journeys unless they are either concerned that they cannot afford to run their car or just like comparing results with others, bragging rights etc.

[Rusty2009]

I'm not fussed by MPG I never even looked at book figures when I brought my car, all I knew was I wanted a 2.0cdti and that's what I got. What MPG it returns doesn't bother me all that matters is I'm happy and enjoy driving it!


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[andy2174]

I did buy my car based on the book mpg, claimed mpg, which was the polar opposite to the RX8 231 I was running, I was getting around 20mpg, when I first got the Astra I was a bit hacked off at only getting around 44mpg, which when you factor in the Astra cost me £8,000 more than the RX8, I could have covered a lot of miles in the RX8 for £8K !

But, now having got used to the Astra I get around 52mpg, which saves me on fuel outlay each month

I cant say I am obsessed with its MPG, but, I do know my journey to work at 530am is a lot more economical than coming home, the roads are lovely and empty going, so I can cruise along at my own pace, coming back home, its full of the blue rinse brigade who are quite happy to bumble along at 43mph, whatever the road speed limit or weather circumstances!

[J1ODYA]

Your friends are morons

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[bruce_19]

@J1ODYA no argument from me haha

As for @stigeye I dot agree with the first line of you comment I can go 2 roads home. 1 the direct one which is 6 miles and I get 29.5 mpg and the other non stop one with is 12 miles and get 32 mpg so the direct route which is the one I use costs me £20 a week and the other which costs about £36 ish a week so over a year is £752 which can pay for insurance and tax for the year and still have some left.

That's what I am getting at that they would do the longer route because they are constantly moving and it takes the same time but it would cost more a year.

Don't get me wrong once Aberdeen finally gets the bypass finished i will get the same mpg as the faster route.

On a clear day I can get door to door in 8 mins and the traffic for me getting 2 and from work is 20-25 mins.

I don't know how bad traffic is in other parts of the country but for me I can't justify the extra cost for no real world gain. I'm not gaining time at home all I would do is put extra miles on the car and waste money on fuel which is what I was getting at in my first post.

[stigeye]

I have yet to meet anyone who would travel twice the distance just because they increase their mpg, they are also increasing the fuel they use and mileage on their car. I cannot for the life of me believe that there are people out there who would double their mileage and increase their spend on fuel and not realize they are doing it?

I don't really get why you chose those two routes in your analogy, you have a direct route which you say you get 29mpg when you start stop along the route and yet you have a non stop route at twice the distance i.e a bypass and only get 32mpg. Even so, I do not believe anyone would consider taking the much longer route unless they are driving a business car and it shortens their journey time considerably.

[bruce_19]

I know many people who travel further than they have too, granted not as far as I would have too. The reason I used that example is because it is my 2 routes home. I don't cover many miles which is why it is double. My boss 50 miles a day so 6 mile extra to his journey doesn't seem as bad as mine.

I used to do the longer route because I could keep the car in gear for longer since I found it hard driving a manual since my car crash I done in my left knee and could hardly walk because if using the clutch. With my Astra being auto I can do the short route without being in too much pain.

Again you are looking far too much into what I have said above.

Its for everyone to work out what works for them all I am saying is just because 1 road can give you better mpg is it better than the shorter road that is what I was getting at.

I do agree with what you are saying why do double with no gain but at the moment with the bypass being put in most of my work colleagues are having to do more miles than they normally do not double but more just because of heavy traffic. I don't know what like traffic is like down your way but I do know what like it is round my way and its an absolute nightmare and has been for years so some people prefer to just keep moving.

Like I said above once the bypass is in my mpg go up to 32 as less traffic and probably journey time half.