Hypermiling

[W3H5]

Share tips and tricks, experiences and ideas.

For those few of you who don't know about hypermiling here's the Wiki article explaining it.

Personally I would prefer to call myself an Ubermiler more than a hypermiler but I'm still running a carb so I really can't.

Techniques I use include not braking over 10kph, avoiding coming to a stop and drafting whenever possible, among others. My exact mpg be yet to calculate and somewhere down the line I will be adding some more aero dynamic additions to increase my hypermiling efficiency.

Note to staff: I searched for this topic but found no threads, if there is a thread and I missed it please redirect me. Cheers.

 

[Bopop4]

Aww yiss this is my type of thread.

I hypermile everyehere with the exception of drafting because of stones flying up and hitting the windshield.

Bought an Ultragauge a few months ago and it's really helped me see exactly how the car is using the fuel. Engine off coasting is the biguest help, along with pretending you don't have any brakes.

Makes for some fun turns whenever you have a guy tailgating you and then after the turn they're 100 metres back.

Last tank I got over 950km in a car where people normally only get 600.

 

[Liquid]

What's the deal about coasting in neutral, does it save petrol or not? My car is a 1999 Honda, for reference of when the engine was built.

I do try and engine brake where I can. Fewer uses of the brake pedal, especially aggressive actions. Stuff like that.

 

[W3H5]

Aggression is usually the worst on fuel mileage. I see idiots racing up to red lights all the time and a few minutes later I'm right behind them at that same red light.

I must confess that I'm kind of cheating a bit by hypermiling on a 114cc scooter. If I have a chance I'm going to switch to a semi-auto with FI which should improve my mileage.

At the moment I'm dong all the calculations in my head which isn't very accurate but I get approx. 160kph from a full, 4ltr tank (Shell Fuelsave gasahol 91). Combined weight of 165kg with me and fuel makes it pretty good.

I don't inflate my tyres often enough and could do with a proper windscreen but overall I'd be better of with a bit more efficient vehicle.

 

[Bopop4]

What's the deal about coasting in neutral, does it save petrol or not? My car is a 1999 Honda, for reference of when the engine was built.

I do try and engine brake where I can. Fewer uses of the brake pedal, especially aggressive actions. Stuff like that.

Even coasting in neutral saves a lot of gas.
With my Focus, it uses .2 gallons per hour at idle vs .3 gph coasting in gear. And it'll roll further in neutral.

The injector shutoff in my car only happens at about 2500rpm, you'd have to get a Scangauge of some sort to see where your car does it.

 

[W3H5]

Would like to know how effective those on-board mileage computers are. I've only ever met one person using the Scangauge, most other people had cheaper alternatives but then I guess the information accuracy is questionable on a lesser computer.

I've been looking for a more accurate way to calculate mileage without using any on-board computers but preferably something a bit more advance than counting km between each fill up. Ideas?

 

[Liquid]

The injector shutoff in my car only happens at about 2500rpm, you'd have to get a Scangauge of some sort to see where your car does it.

If I remember exactly what it displays, my car tells me when it is in economy mode and has lopped off some of the valves. Or a cylinder. Not sure exactly what. But it kicks in around 2500 revs too and a green light flashes on the dash, but that light is out so I need to get that fixed..

 

[Beeblebrox237]

I don't often practise hypermiling, but I'm sure I'll be trying to save as much fuel as possible when I have a car of my own. I tend to drive more for fun than anything when I do drive. However, I have tried to eke out as many MPG as possible, and I tend to follow my instincts (and the instant MPG o'meter). Generally, I try to take advantage of hills as much as possible, and try to be in as low a gear as possible. I'll also try to anticipate what's happening in front of me far, far in advance, so that I can slow to a stop gradually with minimal brake input.

 

[Slash]

I couldn't keep my foot out of it if I wanted to

 

[Adamgp]

I wouldn't call myself a hypermiler, but I do usually try to keep as many bars lit on the mpg gauge as possible.

That is off course, until road rage kicks in.

 

[TenEightyOne]

Coasting in neutral would be pretty stupid, wouldn't it?

 

[Bopop4]

Coasting in neutral would be pretty stupid, wouldn't it?

Not at all, it saves a lot of gas.

 

[Zenith]

With a stick-shift car, don't shift into neutral to roll to a stop.

Think of it this way, when the car is rolling to a stop in gear, the engine is kept running by the momentum of the car. There is no fuel needed.

When the car has the engine in neutral, the engine is supported by itself. It has to idle.

 

[TenEightyOne]

Not at all, it saves a lot of gas.

Wow, that makes it okay then.

I meant from a control point of view more than anything, the time taken to select the gear and apply the throttle to get out of trouble is critical.

And the maths of coast-saving is questionable too.

 

[Bopop4]

Wow, that makes it okay then.

I meant from a control point of view more than anything, the time taken to select the gear and apply the throttle to get out of trouble is critical.

And the maths of coast-saving is questionable too.

If you're in the city or an area where there might be a problem then you can leave it in gear.

Anywhere else where there's a bit of a downhill on a country road I'll let it sit in neutral and watch the MPG go into the 150 range.

That article is so wrong it's laughable.
My car uses .2gph at idle, and even more when it's in gear. 1gph is a 70kmh cruising speed so I'm not sure what the article is going off of.

The DFCO point in my car is 2500rpm, if I take it up to that speed in 5th it's going to be doing 60mph, much too fast for efficient driving on my roads.

I've been coasting in neutral and been doing EOC and I'm getting better overall mileage than the car is supposed to get on the highway, so it's obviously working.

Would like to know how effective those on-board mileage computers are. I've only ever met one person using the Scangauge, most other people had cheaper alternatives but then I guess the information accuracy is questionable on a lesser computer.

The car handles fine in neutral as well, it still handles well even with no power steering.

I've been looking for a more accurate way to calculate mileage without using any on-board computers but preferably something a bit more advance than counting km between each fill up. Ideas?

I use an Ultragauge which is basically a cheaper scangauge, more effective user interface as well.

It's completely changed the way I drive, so much that you're missing by not knowing exactly what's happening.


The best thing is to roll engine off 2km down my road into the driveway.

 

[TenEightyOne]

If you're in the city or an area where there might be a problem then you can leave it in gear.

Anywhere else where there's a bit of a downhill on a country road I'll let it sit in neutral and watch the MPG go into the 150 range.

Haha, you shouldn't be allowed on the road or you should be made to have an old-person's automatic

EDIT: Still can't find a proper site that agrees with you about the benefits of coasting in a modern car versus the very obvious danger you pose, the AA certainly don't.

 

[Bopop4]

Haha, you shouldn't be allowed on the road or you should be made to have an old-person's automatic

EDIT: Still can't find a proper site that agrees with you about the benefits of coasting in a modern car versus the very obvious danger you pose, the AA certainly don't.

There's nothing dangerous about it.
I've never had a single incident because I maintain a large gap to the car in front.
And also that I actually use my mirror and signals.

Driving slower gives you more time to react to potential problems. The way I drive is actually safer than the conventional method.

Again, that other link is inaccurate.
I save more gas coasting out of gear than I do with engine braking. I've tested it and found that there is too much engine braking where leaving it in gear.

You didn't look very hard then, the topic has been beaten to death over at the ecomodder forums and it's been found that EOC is the best, followed by coasting in neutral, and then by engine braking.

 

[TenEightyOne]

The way I drive is actually safer than the conventional method.

No, no it isn't, and the fact that you seem to believe that is worrying for you, your passengers and the property/persons who you encounter on your journeys :\

EDIT: And having read over 30 pages only 5 agree with you, they're written by car fans like you. Others like the AA (linked above, no better expert), Clarkson and the manufacturers say that it uses more fuel in neutral in a modern car than it does when coasting in a high gear.

Add to that the fact that you're not in proper control of your vehicle and it's all a bit worrying.

 

[Leggy1]

I know that some manufacturers are using automatics with a coasting function (shifts into neutral off-throttle). You can get it on VWs, with their latest DSG 'boxes. It is more efficient than staying in gear, but strange for those that are used to having engine braking.

 

[Bopop4]

No, not it isn't, and the fact that you seem to believe that is worrying for you, your passengers and the property/persons who you encounter on your journeys :\

I've never had an accident, I've never come close to an accident with this driving method.
It's simple physics, driving slower is safer, I don't get what's so hard to understand about that.

I have tested these methods extensively to see how safe they were, there are no negatives associated with them.

The only time when driving in neutral adversely affects handles is when you're right on the limit and need to balance the car with some throttle. It has a slight oversteer condition in that trim but it doesn't matter because you're nowhere near the limit in normal driving anyways.

 

[TenEightyOne]

I've never had an accident, I've never come close to an accident with this driving method.
It's simple physics, driving slower is safer, I don't get what's so hard to understand about that.

I have tested these methods extensively to see how safe they were, there are no negatives associated with them.

But if you're at college, how long have you been driving? Pardon me for saying that it doesn't seem very long. You also ask me to accept your extensive testing over the AA?

"Simple physics; driving slower is safer". That's false, I don't know who teaches you physics. It's safer when all things are equal, important distinction.

In normal driving you are instantly able to apply clutch and brake to perform and emergency stop or throttle to provide emergency power. You should practice responding instinctively to either. When you roll with the car out of gear you ensure two things; in an emergency stop you have massively reduced the stopping efficiency of your car. In the event of requiring emergency power you're screwed; you'd have to engage a gear etc while losing reaction time.

Given that you've made both parts of emergency control either significantly weaker or impossible I'd say you need to revisit physics.

 

[TB]

@TenEightyOne - All of your arguments assume that @Bopop4 is in neutral constantly, which I can fairly confidently say he isn't. If he has a lick of sense, and based on his activity here I believe he does, when the situation is questionable or he in traffic, he's not driving irresponsibly.

Regarding his driving experience, I'd wager that despite being significantly younger than I am, he has more intensive driving experience than I due to racing, which I have never done.

 

[TenEightyOne]

@TenEightyOne - All of your arguments assume that @Bopop4 is in neutral constantly, which I can fairly confidently say he isn't. If he has a lick of sense, and based on his activity here I believe he does, when the situation is questionable or he in traffic, he's not driving irresponsibly.

Point taken but I wouldn't make that assumption; drive is clearly required to undertake the journey. I just have a thing about coasting, it really isn't safe

What he said was

The best thing is to roll engine off 2km down my road into the driveway.

Which sounds a significant distance to me. He uses turn signals while coasting which shows there may well be other road users.

@TenEightyOneRegarding his driving experience, I'd wager that despite being significantly younger than I am, he has more intensive driving experience than I due to racing, which I have never done.

Which makes it seem even more odd to me, my own racing experience was where I really learnt how to balance a car, you do things you (hopefully) never do on a road. Except with a girl.

But coasting is up there on my pet hates, it isn't safe and it doesn't make you any gains in a modern car.

 

[Beeblebrox237]

I've coasted in neutral with no problems, but usually the only time I'll be in neutral is when I'm coming to a stop and I don't want to downshift. If I'm slowing to a stop from, say, 40, I'll likely be in fourth or fifth gear. Usually I'll stick it in neutral as the revs drop, rather than putting it in a lower gear and coasting with the clutch out. Heel-toeing is an option in that situation, but only if the car has well placed pedals, and only if you can take a moment to concentrate on rev-matching.

I don't think coasting is dangerous at all as long as it's done safely. I'm used to quite steep hills so I'm used to sticking it in second and letting the car coast in gear at maybe 4000 rpm (about 40), coasting on a hill like that would be fairly silly, but on a gentle grade it's probably a very good option.

 

[Leggy1]

@TenEightyOne http://m.autocar.co.uk/blogs/green-cars/sometimes-it-preferable-coast-through-life

It is more efficient, at least on diesels.

 

[Bopop4]

But if you're at college, how long have you been driving? Pardon me for saying that it doesn't seem very long. You also ask me to accept your extensive testing over the AA?

3 years now. At the start I drove like a normal teenager, and then started to try and save gas because 1. I wouldn't get any tickets, and 2. It would prevent me from doing the things that teenagers normally do with their cars, IE, crash them into another car.

Well the AA has some things wrong like the coasting in neutral, which I have found to be better than coasting in gear. If Leggy's post is correct then manufactures think that way as well.

Also, I'm not saying that all cars are better in neutral, but for my car at least, it uses less fuel to be in neutral.



When I drive with other people it doesn't matter if they've had 4 years or 40 years of driving, they all drive WAY too close to other cars. Can't stand driving with some people because of that.

Things are safer when they are slower. It takes an exponentially longer amount of distance to stop from 50mph vs 25mph.

If you drive 5mph slower than you normally do then you open up a lot of space between you and traffic, and it gives you more time to react to problems. It is also very relaxing when you have a good gap to the person in front of you, calm heads prevail.

In normal driving you are instantly able to apply clutch and brake to perform and emergency stop or throttle to provide emergency power. You should practice responding instinctively to either. When you roll with the car out of gear you ensure two things; in an emergency stop you have massively reduced the stopping efficiency of your car. In the event of requiring emergency power you're screwed; you'd have to engage a gear etc while losing reaction time.

?
In neutral you have just as much stopping power as normal, I have tested braking with the engine off in a safe environment and even without the brake booster I can still perform an emergency stop that is just as effective as being in gear with the engine on.

Which sounds a significant distance to me. He uses turn signals while coasting which shows there may well be other road users.

It is a significant distance, which is why I'm happy when I can pull it off. You can only do it when there's no traffic (Not a very busy road at the time of day that I drive it.), and a slight tailwind. Anytime I have to go around a corner I leave it in gear with the clutch in so that I can react to a problem.
I always use my signals anyways even if there's nobody around, it's good practice.

@TenEightyOne - All of your arguments assume that @Bopop4 is in neutral constantly, which I can fairly confidently say he isn't. If he has a lick of sense, and based on his activity here I believe he does, when the situation is questionable or he in traffic, he's not driving irresponsibly.

Regarding his driving experience, I'd wager that despite being significantly younger than I am, he has more intensive driving experience than I due to racing, which I have never done.

Exactly, getting into an accident is the last thing that I want.
I believe the racing helps to get the speed bug out of my system so that I don't act like a fool on the road. No point in going fast and saving 3 minutes on the road when you can go to a track and save 3 tenths.


And thanks, not many adults actually take young people seriously when it comes to driving techniques.
I do need to work on my parallel parking though...

 

[TenEightyOne]

In neutral you have just as much stopping power as normal, I have tested braking with the engine off in a safe environment and even without the brake booster I can still perform an emergency stop that is just as effective as being in gear with the engine on.

That simply isn't true. Where's your test data?

 

[Leggy1]

That simply isn't true. Where's your test data?

My driving instructor said the car stops slightly better in neutral as the ABS works more effectively without engine braking.

But of course that only applies to modern cars, with the engine on I presume.

 

[TenEightyOne]

My driving instructor said the car stops slightly better in neutral as the ABS works more effectively without engine braking.

But of course that only applies to modern cars, with the engine on I presume.

No, not at all, the engine's effect on braking is additive. If you're at the point where you're using ABS you're in deep crap anyway, especially if your instructor's in the car

 

[Bopop4]

That simply isn't true. Where's your test data?

It is true.
I can get the ABS to engage with the car in neutral, if the wheels are trying to lock it has adequate braking force.
If the engine is running all the systems are still functioning properly, if the engine is off you still get a few good punps on the brake. The first pump with the engine off is just as strong as if the car was running.

No, not at all, the engine's effect on braking is additive.

The only time that matters is if you're brakes are so poor that you need the engine braking. All modern cars can lock the wheels because the brakes are actually good, they don't need engine braking.

If you're at the point where you're using ABS you're in deep crap anyway, especially if your instructor's in the car

Did you ever get driving instruction?
During the emergency maneuvers testing they make you engage the ABS while performing emergency stops to let you see how it works.