any thots on using neutral to coast ?

The brakes are different in N and D!

In N, they use the actual friction brakes.

In D, the regen is used under certain conditions (normal stopping), but friction brakes are used for hard stops and less than 8mph.

I use N on long downhills, but only if there isn't any trafic around.

I think CC is more dangerous than N.

 

yeah, I've owned a stick, but a stick is only "supposed" to be in neutral while "in between" gears.

C'mon squid, what part do you disagree with?
- that it's a violation of the vehicle code?
- that paying attention to D vs N distracts from driving?
- that a vehicle, on a public road, isn't as safe in neutral as it is while under power?

I'm NOT being militant, I'm just get sick of everyone acting "crazy" about getting good MPG, to the point of coasting in N on the roads and highways... Thinking reasonably, wouldn't you agree it's a little extreme?

 

Hm. Are you sure? If you're in neutral, I don't think that MG2 will respond at all to provide you regenerative braking, so the "conventional" brakes will handle braking. Correct me if I'm wrong, but if the car is in Neutral, that necessarily means MG2 is free... it neither drives the car's forward motion, nor provide any regeneration to slow you down. Pressing the brake will not turn MG2 into regen mode...

All that means is that you lose energy that you could have recaptured with regenerative braking, and you wear out your brakes quicker... it also means that your brakes may not be as effective in non-emergency stop situations where regenerative braking would have picked up most of the braking load.

I'll have to try it later... but that's something to consider.

 

You look in your rear view mirror and see a car aproaching much too fast to stop in time. You accellerate to avoid being rear ended.

You are driving down the road and see a car pull out from the left WAY too late to get in front of you. The road is slippery. You can either slam on the brakes or accelerate. This one actually happened to me on Ridge road in Evanston, IL several year ago. I am convinced that if I had hit the brakes, I would have hit the car. By accelerating I was able to drive around her and avoid an accident.

The other aspect has more to do with psychology. In an emergency situation, if we think we are doing the right thing, we will keep doing it, even if it is not working. If an emergency arrises and we think we need to accelerate, we will step on the gas, which is what we have been trained to do since we started driving. If the car is in neutral, it will not accelerate. It is human nature to continue stepping on the gas harder and harder, rather than look around to figure out why it is not working.

Now, with all of that said, these are very rare and unusual situations and I don't know for certain that if I had hit the brakes it would not have been ok.

I sometimes feather the throttle and sometimes use neutral. If it is a long hill or I have a long time to coast down to a slower speed, I will use neutral, rather than trying to hold my foot in a very precise location for an exptended period of time. Also, under some circumstances (like near 40mph or when the battery is low) it is very difficult to get the car in glide mode by feathering the throttle.

So in summary my opinion is that Yes, it is probably illegal in most jurisdictions but I do not consider it a dangerous practice, so I break the law. I use the same logic with respect to speed limit laws. Oh yeah, and i drive bare foot sometimes too

Steve T

 

I disagee that a vehicle, on a public road, isn't as safe in neutral as it is while under power. IMO, that's too nebulous of a statement, for the range of possible driving conditions/environments is just too great to argue. However I will say, that as an experienced crotch rocket pilot, "neutral" is a considered a "gear" just like any other, it has it's time and place. Likewise for various sportscars I've owned.

Although I do agree that some people go a little too nuts and might actually cause a traffic hazard just for the sake of MPG.

 

:lol: LOL - we can disagree on the whole neutral thing, as long as you gave me the part I quoted you on. That was my point really, I just took the long and argumentative route to get there Oh yeah - Hurricane 600, CBR 600F2, with a Nighthawk ( I was having a BAD year) thrown in the middle there somewhere....

 

LMAO... Fine!

Nice to see another hooligan on board!

 

OOPS!

I stand corrected... Although the brakes DO "work" in either scenario (obviously), they do operate a little differently. Tried it at lunch, NO regen while braking in "N"....

 

well, I am not arguing and I am taking all your comments into consideration as I consider you more experienced. The only thing I want to say that I haven never had an instance that I would like to accelerate for the car that is speeding behind me. I mean if he is speeding than I always think that perhaps being in the slow lane is not exactly where he should be and that he should move over to the middle lane and go as fast as he wants to go

 

I've encountered similar situations on Ridge Road myself.
Though I won't get the chance to see exactly how good or badly and howmany laws I'll be breaking while hacking it away and optimizing in my Prius, til '06

 

out of curiosity, has anyone ever tried a good old fashioned test? Ifyou have a stretch of your commute that would be perfect for this, pipe up.

ideally, we'd have a nice long gentle slop with a stopsign at the end. now, from the same spot at the same speed, one day you should kick it into neutral, and see what you are looking at for instant mpg. the next day, try it in B. i'd be interested to know just how much difference we are talking about. it being worthwhile could easily depend on if you are fully charged, or if you can take advantage of regen, but i'd love to see what numbers you all come up with if you have fully charged packs.

 

I love these discussions! They go on for pages and pages and nothing changes. I think both are valid though one may or may not be illegal in some states. One could make an argument that since the Prius does not have a "transmission" in the ordinary sense of the word that the law does not apply and the car is not in "neutral" as in a manual transmission ! Lawyers love arguments this could go on for days. :blink:

 

As others pointed out: driver distracted by additional shifting; a sudden need for power, delayed because one was in N and not D.

I don't know how much these possibilities contribute to accidents. Now that cars have black boxes we should start to see statistics about it.

 

"Don't forget your Prius has a Black Box and will record the last 5 seconds before impact. "

This is the most compelling argument I have seen. Right or wrong, anything you do may be used against you, and this can't help.

 

I've been wishing for the same thing these last few days. (Maybe I just need more practice, but I'm finding that feathering the accelerator is only easy on flat, level roads. I get "no arrows," think "Cool, I'm gliding," and then half a block later there's this gentle upward slope.....)

My idea is to put it in the cruise control lever. Just pull and hold in the CC "cancel" position, and WHAM!, no arrows, regardless of slope.

Now if I could just move the CC lever to the steering column so it doesn't turn with the wheel.....

 

I'm confused:

Why would you coast in neutral and not reep the benefits of charging the battery pack while coasting in drive?

 

I believe the 55+ club (not age) is n-coasting when even they can to maximize mileage. n-coasting moves the car with the least amount of energy. d-coasting reduces the distance the car travels but, regens. In traffic, you're continually applying the brakes and regenning (I just made that up--is it 1 or 2 n's) and that activity should keep the battery charged. e-coast when ever you can to maximize mileage w/o being a nuisance to the other people on the road.

 

Just want to throw in my "Emergency Vehcile" driving (as a trainer) experience in.

After a rapid lane change avoidance, a la -object pulls out or falls in front of you, the rear of the car becomes light and will more easily skid. This is a result of your natural surprise action of "foot off gas" causing weight shift to the front plus sudden lateral forces on the tire. By gently pushing on the gas after you have swerved, you add weight to the rear and stabilize the car. In "N", this slight benefit would be lost to you. That is the only time I have needed acceleration to get out of a problem.