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Hi,

I primarily drive an 89 Corolla which seems like it's always having some engine trouble that limits mileage performance, but also sometimes I drive my wife's 97 Civic. I can consistently get 45-50mpg in the Civic on my commute.

My motivation in hypermiling is social. I don't particularly care about the dollar or two that I save a month by saving gas, but I do care about the emissions I produce and the politics of oil.

I'm fairly moderate for someone claiming to hypermile. For example, I consider it wrong to cause "real congestion." An example of "real congestion" would be slowing into a glide while approaching a freeway off-ramp, such that a line of cars behind me is forced to decelerate below the normal range of traffic speed even if they are not heading for my exit. Slowing down on the ramp is fine as long as it doesn't create a line that extends significantly onto the freeway (i.e. depends on conditions). "Imaginary congestion" would be gliding up to a red light irrespective of the wishes of the driver behind me to "hurry up and wait," and I will glide towards the light every time, unless perhaps it's possible the driver wants to right-on-red, in which case I'll weigh his needs against mine.

Also, I make it a rule to never roll through intersections. That is my rule, but it gets broken every day! Certainly rolling a stop at 5 mph is safe if no one is there, right? If so, certainly rolling at 10 mph is safe if the visibility is great while approaching the stop. So hard to keep the line from getting blurry...

Generally I don't mind tailgaters, but I am annoyed by drivers who ride my bumper despite the availability of another lane. Is tailgating just about ego? ("You're in my way, butthead, so take this!" "Oh no, don't get so close, that really hurts.")

Lately I've been biking to work 3 days a week, which makes it tempting to say something like "my effective mileage is like 90 mpg," although that would not be very true.

Cheers,
Chris

welcome Chris, Those civics are great cars! Riding the bike to work is a great thing also!

...I make it a rule to never roll through intersections. That is my rule, but it gets broken every day! Certainly rolling a stop at 5 mph is safe if no one is there, right? If so, certainly rolling at 10 mph is safe if the visibility is great while approaching the stop. So hard to keep the line from getting blurry...

Cheers,
Chris

I and many others here take the high road on this one. As hypermilers we have to defend our actions to those who either don't understand or don't agree with our goals. Obey ALL traffic signs. Including STOP signs and traffic lights. The fuel you might save isn't worth the loss of a life, damage to your vehicle, a moving violation or an increase in your insurance.

If you choose to break the law don't attribute it to something you learned here. You asked.

Welcome Chris and with some time here you won't want to do extreme techniques when expert techniques will suffice. Glad to have you here. :D - Dale

I and many others here take the high road on this one. As hypermilers we have to defend our actions to those who either don't understand or don't agree with our goals. Obey ALL traffic signs. Including STOP signs and traffic lights. The fuel you might save isn't worth the loss of a life, damage to your vehicle, a moving violation or an increase in your insurance.

If you choose to break the law don't attribute it to something you learned here. You asked.

Welcome Chris and with some time here you won't want to do extreme techniques when expert techniques will suffice. Glad to have you here. :D - Dale

I know what you mean. I like the high road best. However I've been doing this since I started driving (failed the driving test the first time for doing a rolling stop turning right at a stop sign), so this didn't start with hypermiling. There's a certain number of times you can do something before it becomes a habit. Knowing that I'm wrong and forcing myself to change are on different levels.

I'm a hypocrite on this issue as well, if I keep doing it. Recently on my bike a Jeep rolled into the roadway at 15mph and came very close to hitting me. He was on a collision course but when I screamed at him he slammed on his brakes and I was able to maneuver around him. Isn't that a perfect example of why not to roll stops? (Er, maybe I'm not such a hypocrite because I look where I'm going before proceeding, and I don't roll through at 15... or at least I don't think I do?) (Another note here: cyclists can be a bit smarter than I was, I didn't react to the Jeep until it was almost on top of me, but I could have slowed down earlier and left myself an out - maybe I'll learn.)

Anyways, I'm not totally convinced that the highest of the high roads is the right one: there are plenty of stops where I agree that a full stop is the best thing, generally any time I'm expected to yield because this means the traffic may be moving quickly, but on the other hand with 4-way stops a complete stop is quite tedious and I doubt that it's really necessary. Nonetheless, this is a really slippery slope, either I really have to force myself to completely stop whenever it's legally required or I have to draw some other firm boundary - i.e. limit myself to 5 mph at the "stopping" point, e.g. be slow enough that stopping is always possible and I have plenty of time to observe all the traffic routes. (Still I need to discipline myself to practice what I preach.) I do roll the same types of stops on a bike in the same fashion, although the bike has an additional incentive for doing this - not wanting to put a foot down.

I can't support your decision or rationalize the reasons for doing this illegal maneuver. What I can do and others here on this site can do is offer you better, more effective, legal in all 50 states techniques.

I looked at your blog listed in your sig and checked out your Hypermiling article. Good job, I hope you become an active member here. I would like to offer some "learned" tips that may help you.

I often recommend to others pumping up the tires to max sidewall PSI and leaving the decision of exceeding this amount with the individual, while acknowledging that some have went to 60psi or higher having no problems if the tire is in excellent condition.

Telling someone to intentionally exceed a safety limit posted on the sidewall could make you liable for their actions. I don't know the condition of their tires, vehicle or even their reasoning ability in regards to safety. It's safer to recommend the sidewall limit and acknowledge higher examples.

By promoting hypermiling as a recognized term and group of techniques I am always considerate of how others may interrupt my advice, it doesn't benefit anyone who hypermiles if we are considered dangerous in our practices.

In regards to enough time to stop the engine at an intersection, it is relative to two or three things, number of cylinders, carburetor or injection and safety.

For my throttle body injected 3 cylinder Metro if I'm sitting for more than 4-5 seconds I will begin benefiting from a FAS at an intersection IF I can safely get the car restarted before the light changes.

For a 1969 Ford Mustang with a Holly 850cfm double pumper it will need to dump a lot more gas into the intake to get it restarted so you may need a 15-20 second light.

These are my examples of extremes. Generally I add 1 or 2 seconds on to the number of cylinders if it is fuel injected as a guideline for FASing at an intersection. A 6 cylinder FI needs about 7 or 8 seconds of red light before it saves fuel.

If a car, for example, a 89 Toyota Corolla 4 cylinder has a carburetor I just double the cylinder count. 8 Seconds. It's a good starting point.


Hope this helps. :D - Dale

I can't support your decision or rationalize the reasons for doing this illegal maneuver. What I can do and others here on this site can do is offer you better, more effective, legal in all 50 states techniques.

I looked at your blog listed in your sig and checked out your Hypermiling article. Good job, I hope you become an active member here. I would like to offer some "learned" tips that may help you.

I often recommend to others pumping up the tires to max sidewall PSI and leaving the decision of exceeding this amount with the individual, while acknowledging that some have went to 60psi or higher having no problems if the tire is in excellent condition.

Telling someone to intentionally exceed a safety limit posted on the sidewall could make you liable for their actions. I don't know the condition of their tires, vehicle or even their reasoning ability in regards to safety. It's safer to recommend the sidewall limit and acknowledge higher examples.

By promoting hypermiling as a recognized term and group of techniques I am always considerate of how others may interrupt my advice, it doesn't benefit anyone who hypermiles if we are considered dangerous in our practices.

In regards to enough time to stop the engine at an intersection, it is relative to two or three things, number of cylinders, carburetor or injection and safety.

For my throttle body injected 3 cylinder Metro if I'm sitting for more than 4-5 seconds I will begin benefiting from a FAS at an intersection IF I can safely get the car restarted before the light changes.

For a 1969 Ford Mustang with a Holly 850cfm double pumper it will need to dump a lot more gas into the intake to get it restarted so you may need a 15-20 second light.

These are my examples of extremes. Generally I add 1 or 2 seconds on to the number of cylinders if it is fuel injected as a guideline for FASing at an intersection. A 6 cylinder FI needs about 7 or 8 seconds of red light before it saves fuel.

If a car, for example, a 89 Toyota Corolla 4 cylinder has a carburetor I just double the cylinder count. 8 Seconds. It's a good starting point.


Hope this helps. :D - Dale

Thanks Dale. I'll be re-reading myself. I seldom write things the way I mean to the first time around...

Does your calculation of FAS ROI consider the battery's state of charge? I'm not even sure if it's significant, but it could count for several seconds.

On liability, I agree that legally you're correct, but are you aware of any actual cases in which a blogger was held liable for potentially dangerous advice? This might be a bit of an academic question, I may well adopt your stance regardless, and I understand your point.

On legality, I think your point is that a rolling stop is not what you call hypermiling technique. I see your point and I certainly wouldn't promote it that way. The fuel gains are very small, over the number of intersections and low speeds at which I might consider the practice to be truly safe. (And the fuel gains over dangerous maneuvers are just stupid.) Still I find myself wondering if the majority of hypermilers really hold that view rigidly in practice, (am I the only confessor?) although probably the same can be said about anyone whether they hypermile or not.

If that wasn't your point, we may have to agree to disagree on certain laws. To me, "legality" is an insignificant word in comparison to "safety." I also break speed-limits at times. By way of contrast, I can think of one perfectly legal, yet very dangerous maneuver that is not discussed often enough - passing on a 2-lane highway, and I take a very conservative approach to it, if I do it at all.

Thanks,
Chris

I assume as with most things like this, you are the only confessor. I don't want to see you be the sacrificial slamb.

I'm not sure if I follow about the state of charge?

Being that anything said on the internet is more or less permanent it may come back to bite you, I really don't know if unintentionally dangerous advice would actually make you culpable but not saying it will make you innocent. :D - Dale

What I meant by state-of-charge is that energy is withdrawn from the battery during a start. That energy will be replenished from gas later on.

But nevermind. I did a back-of-the envelope calc and it's nowhere close; probably only around 0.1 seconds of idle-time. (Assuming 300 W starter cranking for 0.5 seconds, 30% ICE efficiency, 50% for the alternator-times-battery-cycle efficiency, 132 MJ/US gal for gasoline energy density, compared to an engine idling at 0.3 GPH.) Some of my assumptions might not be great, especially cranking duration and battery-cycle efficiency, but a 1 second equivalence is way on the outside.

I would have no way of knowing if that is right. I don't really have an area of expertise but if I did It wouldn't be that. I'm going to go play with a stick or something. :D - Dale