The all new - My relative petrol bill reduced by 25% thread

dnme

I achieved that reduction this week. Here's how.

1. I use a good tyre gauge once or twice a week to check my tyre pressure. I keep the tyres about 1psi above recommended.

2. I emptied out all the crap in my car. Any excess weight has got to go.

3. I drive at a maximum speed to 55mph but try and hold it at 50mph.

4. Close all windows, use the car's heater for air.

Over the past few weeks I have done the brimmed tank measurement and compared my normal driving habits with the above new driving regime. Here are the figures....

Normal driving: 30-34mpg (avg)
====================
This is normally 60-70mph, don't care about weight, carry coal/briquettes around (forgetting stuff is in the boot). Tyre pressures unchecked(one rear tyre had a slow puncture and was at 15psi:eek:)

New Regime Driving: 42mpg avg
=====================
The main problem is the cars behind you. I use the hard shoulder to pull in whenever I can to let cars by but it's not always possible. It's also psychologically tricky to keep a car at 50mph but you do get used to it and it has an overall calming effect.

My mpg saving equates to 31% but being realistic, lets call it 25% to allow for some inefficient driving. So effectively I am paying €1.50 -25% per litre which equals €1.13.

I understand some value their time more than the potential savings. I understand some are simply in a hurry. I'm just posting this as an option. It's merely an article describing what I am doing and how I am taking some control as a consumer up against the mighty oil oligarchy.

I have learned to take my time. I don't measure my time in terms of money. I am a rural lad and seldom drive on motorways. So the above might be more suited to me than some, but hey it's a possibility. It's there for discussion.

-Chris-

This thread was spoiled by pedantry the last time.

Please iet's try and reply in the spirit of the thread/post rather than questioning individual words etc.

Kristopherus

I was wondering was I losing it when I saw only 1 reply;) Well done OP. If we had a bit more innovative motoring behaviour like yours we would all be better off in the pocket.

btkm8unsl0w5r4

-Chris- wrote: »

This thread was spoiled by pedantry the last time.

Please iet's try and reply in the spirit of the thread/post rather than questioning individual words etc.

I think it was spoiled by pedantry with the first post

-Chris-

The next post that isn't directly related to the subject at hand and in the spirit of the thread will merit that poster a 7 day ban.

Fairly warned, be thee, says I.

dnme

dnme wrote: »

I achieved that reduction this week. Here's how.

1. I use a good tyre gauge once or twice a week to check my tyre pressure. I keep the tyres about 1psi above recommended.

Did you always keep the tyres inflated like this or was it just since you focussed on achieving max economy?

Snaggerman

Been thinking about this myself for a while now. Good thread OP, food for thought and all that.
On a related note, did I not hear there was a conventional wisdom of keeping your revs to a certain limit (2650 or thereabouts) to maximise your fuel consumption? Anyone know anything about this?

dnme

Yea thanks Kristopherus,

I have to admit it is not always easy keeping her at 50-55mph, but I find I am getting used to it. Also the way I use the pedal seems to help. You can often ease off a little on the pedal and the car will maintain it's speed, when going downhill, ease off the pedal a good bit. I am basically trying to keep the car at a nice even speed with as little pedal input as possible.

Another great advantage of driving at 50-55 is that you do less breaking and require less breaking effort. I find for example when I am coming into Castlebaldwin village, I just ease off the accelerator pedal and it slows down to to village speed limit all by itself.

EDIT: RJ I just recently started policing my tyre pressure

-Corkie-

Actually most haulage companies are now limiting their trucks to 80kph in order to save fuel as opposed to the old 91kph.

Peasent was saying this also a few weeks ago about driving a different route to work and driving slower aswell and he saved fuel aswell.

newmug

Great idea OP!

Which factor do you think is contributing most to your savings? Is it the reduced speed, the consistent tyre pressure, the reduced weight? Might it be an idea to concentrate on just ONE of these at a time as an experiment to single out which one is most useful?

dnme

newmug wrote: »

Great idea OP!

Which factor do you think is contributing most to your savings? Is it the reduced speed, the consistent tyre pressure, the reduced weight? Might it be an idea to concentrate on just ONE of these at a time as an experiment to single out which one is most useful?

I'd say the single biggest thing is the speed. Finding your cars sweet spot is the key. They reckon for most petrol engines it's somewhere between 50 and 60 mph. Snaggerman eludes to this is his post above, I reckon his engine rev figures might correspond with my mph figures.

But really it's the combination of speed and nice steady even driving. Easy breaking and a nice light foot. Keep easing off the accelerator until the car starts to loose speed, then maintain speed at that point on the pedal.

BigEejit

Fair play to the OP, thats a massive saving. I'd say the road rage you experience must be unreal.

I dont carry crud in the boot (she sits in the passenger seat mostly ) but I have reduced my motorway speeds from 85mph (ish ) down to 70ish and stay in 5th gear and 4th gear at lower speeds than I used to. I would guess that I get 10 - 20% more out of a tank.

But its actually getting harder to keep the speed down. I have noticed quite a dip in the number of drivers on the A21 and M25 over here, far less traffic on the roads. I would suspect that for a lot of drivers the trains (which used to be quite overpriced) are now making financial sense.

kenmason

Without knowing your size of engine, whether it is petrol or diesel, or the types of journeys you make your savings may be good or there may be room for further improvement. I drive a diesel VW Sharan 7 seater which has computer readouts for average fuel consumption etc. and I usually average about 46mpg on my journey from just outside London to the far end of the Beara Peninsula in West Cork, even fully loaded. On the return journey I can average 50mpg from Beara to the outskirts of Cork City despite having to climb quite alot of hills, but for every hill one climbs there is always the downward slope to do a bit of freewheeling. The major factor though is that I am able to keep moving with no traffic lights for over 80 miles.

C4Kid

Dnme

Well done on the results , I've been practising some ecodriving myself, over the last few weeks, and I know how difficult it is to decipline Yourself and not get distracted by others putting You off. The way fuel is going I'm surprised that so many people think it's a waste of time and pointless, but yet complain about fuel and their MPG being lower then specified in the book.It can achieve decent results without drastic changes to Your driving. At least it's a step in the right direction !

ShadowHearth

newmug wrote: »

Great idea OP!

Which factor do you think is contributing most to your savings? Is it the reduced speed, the consistent tyre pressure, the reduced weight? Might it be an idea to concentrate on just ONE of these at a time as an experiment to single out which one is most useful?

All added up.

Moust important thing is keeping it stable. No rapid acceleration, no fast breaking. No speed changing every 10 secs. Like op said, keep it at 50 mph.

Opened windows add up alot!!! You don't notice, but it's fudging up aerodynamic of a car badly!

I tryed to do it with skyline. Keeping it of boost. Steady etc. It game me better mpg, but it's really hard to keep that car of boost....

peasant

newmug wrote: »

Which factor do you think is contributing most to your savings? Is it the reduced speed, the consistent tyre pressure, the reduced weight? Might it be an idea to concentrate on just ONE of these at a time as an experiment to single out which one is most useful?

The single biggest factor has to be the speed, as air resistance rises exponentially (or to the square or whatever ...either way ..not linear) ..but as they say, every little helps.

dnme

Believe it or not, the road rage issue is not too bad. Maybe it's a Sligo Leitrim Roscommon thing :rolleyes:
I pull in if I can on a hard shoulder, but also the roads are fairly empty these days (tg) and I can sometimes travel all the way into Carrick-On-Shannon without a single vehicle in my mirror.

Plus, if you think about it, I am doing 50-55, that's only 5-10 off the legal limit. So I am not going that slow, if someone wants to roadrage me at that speed on the n4 coming out of Boyle, that's really their problem. I am considerate but I won't be bullied by anyone.

dnme

dnme wrote: »

I achieved that reduction this week. Here's how.

1. I use a good tyre gauge once or twice a week to check my tyre pressure. I keep the tyres about 1psi above recommended.

2. I emptied out all the crap in my car. Any excess weight has got to go.

3. I drive at a maximum speed to 55mph but try and hold it at 50mph.

4. Close all windows, use the car's heater for air.

.

I reckon point 1 is negligible as no doubt the tyres were pumped up to the recommended pressure anyway. Point 2, obviously depends on what stuff was in the car. Seems as it's early March point 4 is negligible too as folks generally don't have their windows open in the early Spring.

So it's the lightfoot and reduction in speed did it in my view.

Big Nasty

I refuse to change my driving style - as I said in another thread I like driving and I find the practices mentioned make driving mind numbingly boring. I do have a middle ground solution though. In my local Superquinn if I spend more than €50 I get a voucher for 5c / ltr off my next 50L purchase of fuel. Went in this eveneing and bought €50 worth of beer and then got 50L of fuel and saved me €2.50!

Big Nasty

RoverJames wrote: »

I reckon point 1 is negligible as no doubt the tyres were pumped up to the recommended pressure anyway. Point 2, obviously depends on what stuff was in the car. Seems as it's early March point 4 is negligible too as folks generally don't have their windows open in the early Spring.

So it's the lightfoot and reduction in speed did it in my view.

I.e: Breaking News: Driving Slower Saves Fuel!:p

BigEejit

MCMLXXV wrote: »

I refuse to change my driving style - as I said in another thread I like driving and I find the practices mentioned make driving mind numbingly boring. I do have a middle ground solution though. In my local Superquinn if I spend more than €50 I get a voucher for 5c / ltr off my next 50L purchase of fuel. Went in this eveneing and bought €50 worth of beer and then got 50L of fuel and saved me €2.50!

Even with 5p off a liter (local tesco does it near me) its still £1.29 or £1.30 a liter. Just too expensive for fast driving.

Great thread op. I have been practising some of the same things myself. I am driving 3 years now and have finally gotten rid(for the most part!) of my lead foot issues! Tyre psi 1 above the recommended cant hurt/be dangerous either...can it?!

Question about tow hitches. i got my car ( a 1ton-ish) corolla(e10 hatchback) second hand and it has a hitch i will never use attached. How much do they weigh typically? worth removing to save weight and thus fuel? are hitches welded on or bolted?(yes i will check tommorrow, but i want to know now!!)

BigEejit

BigEejit wrote: »

its still £1.29 or £1.30 a liter.

:eek: where are you getting your petrol that cheap?

edit: oh i see, its in pounds, how odd...

Big Nasty

BigEejit wrote: »

Even with 5p off a liter (local tesco does it near me) its still £1.29 or £1.30 a liter. Just too expensive for fast driving.

Yeah, but they've got a good deal on the beer too so 'win-win'!;)

dnme

Deleted User wrote: »

Great thread op. I have been practising some of the same things myself. I am driving 3 years now and have finally gotten rid(for the most part!) of my lead foot issues! Tyre psi 1 above the recommended cant hurt/be dangerous either...can it?!

Question about tow hitches. i got my car ( a 1ton-ish) corolla(e10 hatchback) second hand and it has a hitch i will never use attached. How much do they weigh typically? worth removing to save weight and thus fuel? are hitches welded on or bolted?(yes i will check tommorrow, but i want to know now!!)

I'd keep the hitch mate, they are always handy and wont affect weight that much. Just think when you join a band and are lugging all that gear, or you get a dog and a dog trailer, or you discover the joys of caravaning, or you start buying calves at the local mart.

:rolleyes:

shedweller

dnme wrote: »

I'd say the single biggest thing is the speed. Finding your cars sweet spot is the key. They reckon for most petrol engines it's somewhere between 50 and 60 mph. Snaggerman eludes to this is his post above, I reckon his engine rev figures might correspond with my mph figures.

But really it's the combination of speed and nice steady even driving. Easy breaking and a nice light foot. Keep easing off the accelerator until the car starts to loose speed, then maintain speed at that point on the pedal.

I recall the pro hypermilers referring to a BSFC (brake specific fuel consumption) chart to find the sweet spot. It looks like a contour map and with this you can find the ideal speed to drive at and get the best out of the engine. I couldn't find any for my yoke though but you may have better luck with more popular engines.
My average speed is minimally slower and i take just a few mins more to get to work. I fill up every two to three weeks now and get 800 miles per 45 litre tank. I got over the need for speed a long time ago when i realised i wasn't gaining much time by speeding.

dnme

dnme wrote: »

I'd keep the hitch mate, they are always handy and wont affect weight that much. Just think when you join a band and are lugging all that gear, or you get a dog and a dog trailer, or you discover the joys of caravaning, or you start buying calves at the local mart.

:rolleyes:

I already do all of those things

Actually i think i will take it off tommorrow and try and sell it

dnme

Deleted User wrote: »

I already do all of those things

Actually i think i will take it off tommorrow and try and sell it

I tell ya what, if you had the e11 instead of the e10, I'd buy it off ya.

shedweller

Maybe keep on topic......for once...on a thread of this kind......please?

galwaytt

well, we've been following elements of OP's post, and it does help.

Car is kept emptied.
Tyres slightly over-inflated over normal (it says to do this for economy, in the car's handbook btw.....)
50mph too slow for top gear, and below peak torque, 70mph too fast. It's more important I find, to drive the engine by rpm, not roadspeed, irrespective of gear......if you're going too slow for 6th gear, use 5th/4th, but keep engine at peak torque. Rev so that on letting out clutch in the new gear, you're right on peak torque - so that means +200rpm on the lower gear........if you follow me.....
Gentle acceleration: imagine, if you will (if you're old enough to remember !), that it's got a carb, and you're trying to NOT activate the accelerator pump on it, but increasing rpm gradually..........or, in the case of SU's......that the damping oil is gone from the piston.........:p

Finally, the biggest difference ? Aircon/Climate, off. Saves 3mpg alone.

Correction: biggest difference: use the car less. Car is now doing, I'd guess, 50 miles a week less by NOT going to the local shop at the drop of a hat.

I'm currently doing a tank-tank run on the Harley to see how that goes atmo.......

Big Nasty

galwaytt wrote: »

well, we've been following elements of OP's post, and it does help.

Car is kept emptied.
Tyres slightly over-inflated over normal (it says to do this for economy, in the car's handbook btw.....)
50mph too slow for top gear, and below peak torque, 70mph too fast. It's more important I find, to drive the engine by rpm, not roadspeed, irrespective of gear......if you're going too slow for 6th gear, use 5th/4th, but keep engine at peak torque. Rev so that on letting out clutch in the new gear, you're right on peak torque - so that means +200rpm on the lower gear........if you follow me.....
Gentle acceleration: imagine, if you will (if you're old enough to remember !), that it's got a carb, and you're trying to NOT activate the accelerator pump on it, but increasing rpm gradually..........or, in the case of SU's......that the damping oil is gone from the piston.........:p

Finally, the biggest difference ? Aircon/Climate, off. Saves 3mpg alone.

Correction: biggest difference: use the car less. Car is now doing, I'd guess, 50 miles a week less by NOT going to the local shop at the drop of a hat.

I'm currently doing a tank-tank run on the Harley to see how that goes atmo.......

Made little sense of that - you just back from the local galwaytt?

galwaytt

MCMLXXV wrote: »

Made little sense of that - you just back from the local galwaytt?

Er, no. Which bit ?


The gearchanges:......if you're engine gives peak torque at 2000 rpm, I'd drive it to 2200 rpm and then change gear -smoothly- and then I'd be hitting the next higher gear right on peak - 2000rpm again........

Big Nasty

galwaytt wrote: »

Er, no. Which bit ?


The gearchanges:......if you're engine gives peak torque at 2000 rpm, I'd drive it to 2200 rpm and then change gear -smoothly- and then I'd be hitting the next higher gear right on peak - 2000rpm again........

Just me so - never mind!

galwaytt

MCMLXXV wrote: »

Just me so - never mind!

...are you sure it isn't you who's been down the local........... ??

ArphaRima

I would have thought that most of what you have done is basic motoring. Not transporting rubbish, keeping correct tyre pressures, not rolling down the windows etc..
There is nothing new but common sense there.

As part of my weekly checks I check oil, tyre pressures and treads, washer fluids; basic stuff. Yay for me.

Sure my driving style influences mpg. But I just dont care about mpg. If I did I wouldnt drive a V8.
I have no problem with the principles of smooth driving, no harsh acceleration or deceleration; measured, tempered driving. Where I disagree with you is with your driving at 50mph. To me that's where your penny-pinching is inconveniencing others. I dont think it's cool to be cheap like that, and I dont like that there is a sub-culture promoting it to that degree.

To be fair though that's just my opinion too.
I would much prefer for speed to not be used as a factor in this. Just keep that as a constant and use every other method. That way you get the most benefit without inconveniencing others.
That would make me a happy motorist. I'll still be overtaking you with prejudice, but at least it will just be you and not a line of 10 cars frustrated by your pace.

I guess what I am trying to say is that surely the discussion can include digressing views and alternative methods of increasing mpg.

dnme

fluffer wrote: »

I would have thought that most of what you have done is basic motoring. Not transporting rubbish, keeping correct tyre pressures, not rolling down the windows etc..
There is nothing new but common sense there.

As part of my weekly checks I check oil, tyre pressures and treads, washer fluids; basic stuff. Yay for me.

Sure my driving style influences mpg. But I just dont care about mpg. If I did I wouldn't drive a V8.
I have no problem with the principles of smooth driving, no harsh acceleration or deceleration; measured, tempered driving. Where I disagree with you is with your driving at 50mph. To me that's where your penny-pinching is inconveniencing others. I dont think it's cool to be cheap like that, and I dont like that there is a sub-culture promoting it to that degree.

To be fair though that's just my opinion too.
I would much prefer for speed to not be used as a factor in this. Just keep that as a constant and use every other method. That way you get the most benefit without inconveniencing others.
That would make me a happy motorist. I'll still be overtaking you with prejudice, but at least it will just be you and not a line of 10 cars frustrated by your pace.

I guess what I am trying to say is that surely the discussion can include digressing views and alternative methods of increasing mpg.

Yes of course it can.

I'm unemployed and need every penny. And imagine where I'll be when it's €2 a litre.

I have never had a convoy of 10 cars stuck behind me. I pulll in whenever I can and the traffic on my roads these days is very light.
But also bear in mind that I am driving very close to the legal speed limit anyway so it's not that slow. For me, the speed limit is a limit, not a target.

My car operates must efficiently at somewhere in the low 50'smph. That's just a fact.

Finally, this is just an experiment. I am not trying to influence or persuade. As I said in my OP, it's just an option that interest some people and generate discussion.