07-25-2008, 04:06 PM
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#11 (permalink)
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Master EcoModder
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If power assist was the reason eocing is dangerous then power assist would be mandatory on all vehicles.
The potential rear-ending accident example presented earlier would not be caused by coasting per se, but by the driver not being aware of his surroundings and driving accordingly.
I got rear-ended once, there was traffic ahead and the guy behind me wasn't looking when I braked. I am pretty sure most rear-ending accidents happen when there is a sudden change in the speed differential between 2 vehicles following each other. A situation that hardly ever happen when coasting out of gear.
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07-25-2008, 04:27 PM
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#12 (permalink)
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Hypermiler
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Ah, I see. You're talking about coasting more than stopped engine-off.
It's a design decision, but my Odyssey has lead-weight heavy steering without the assist. My civic, on the other hand, is barely any different. If the van was designed differently, it could be (nearly) as easy as the civic.
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07-25-2008, 05:03 PM
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#13 (permalink)
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Master EcoModder
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Quote:
Originally Posted by MazdaMatt
Also, at a stop light if the guy behind you loses his brakes or is out to lunch, or is scolding the children in the back of her suv and doesn't see the light. I stare in my rear-view when I'm at a stop. Never know... that's why I'd rather idle at a stop light if there is any traffic. Saving gas should never trump saving your @ss
Steering is definately a major concern. My car is TOUGH to steer without power assist.
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That's how my dad avoided a large multi-car rear endings. When he was dating my mom back in HS. '74 Camaro, big block 396, regular bracket racer. One day, he up and ran a red light, and my mom was furious as to why. Turns out a medium duty truck rear ended a car 2 cars back, and pushed a few cars into the intersection.
In traffic I don't engine brake or sit in N (auto), too much going on around me. But engine off is entirely out of the question on my car. I've been in it when it's stalled out mid turn, no bueno with no power steering.
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Lets see how far it can go
"All I know about music is that not many people ever really hear it. [...] But the man who creates the music is hearing something else, is dealing with the roar rising from the void and imposing order on it as it hits the air. What is evoked in him, then, is of another order, more terrible because it has no words, and triumphant, too, for the same reason. And his triumph, when he triumphs, is ours." -Sonny's Blues
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07-25-2008, 05:24 PM
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#14 (permalink)
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Ex-lurker
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Steering my car is no biggie without power, just takes actual force of hand+arm instead of 1 finger. Braking is something that I won't try at anything > 15 mph without vacuum. I may do the extended vacuum canister mod at some point.
From N to D while engine on in my auto tranny = .5 seconds and i'm out of there if need be.
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07-25-2008, 06:21 PM
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#15 (permalink)
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Pokémoderator
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tasdrouille -
Quote:
Originally Posted by tasdrouille
It is often argued that out of gear coasting, be it in neutral or with the engine off, is dangerous, and even illegal in some places.
Why is that exactly? I have a hard time figuring that out.
The main argument I heard is that you are SOL if sudden acceleration is needed as an evasive maneuver. When exactly do you need to "accelerate suddenly as an evasive maneuver"? You might need to getting out of a driveway crossing oncoming traffic, but that's not quite a situation where you would be coasting. I tried to ask myself this question in a coasting situation, and I wasn't able to find any.
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Here's my take. In the not so long-ago past, cars had lousy brakes. Trucks going downhill could become runaways without in-gear engine braking. Sooooo, laws requiring cars to always be in gear made sense. Cars of today are better, and almost all have power steering/brakes as standard. From my POV, the answer always depends on these three things :
Power Steering : If you have a light car like my Saturn, which was offered without power steering in it's base configuration, then a power steering delete can negate that issue.
Power Brakes : As we have seen in other threads, you can augment your power brakes with additional home made or aftermarket vacuum canisters.
Driving Context : This is the biggest issue, IMO. If you live in a rural area, you can use EOffC much more because traffic density is so much lower. If you live in urban areas, EOffC opportunities are few and far between. In a manual transmission, I do think you can get away with EOnC, because you have to physically downshift to initiate emergency acceleration anyway.
CarloSW2
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07-26-2008, 12:45 AM
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#16 (permalink)
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EcoModding Apprentice
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i don't try and take any sharp turns with the engine off.
i drive a truck and can easily steer it and stop it with no power, and i'm not extremely strong. My brakes last long enough to when i turn it back on. If i park on top of a hill and coast down to the stopsign then brake then coast to the next one and stop, then start it takes alot of work to stop it but is feasable.
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07-26-2008, 01:27 AM
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#17 (permalink)
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Legend in my own mind
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I believe what people need to do is argue that EOC is dangerous in their situation because ...
I find myself Eocing and automatic for distances up to 3/4 of a mile, its what my commute allows, I usually am never on the brake until the last 500 feet or so, my biggest heart skip is starting the engine while the car is still rolling, that creeps me out.
Now as far as the rear end scenario, I guess I grew up differently, that means the driver behind you is at fault and I automatically see body mods and vehicle improvement when something like that occurs.
So with enough of us on here now it would be an interesting statistic to chart.... Accidents CAUSED by Ecomodding, my guess is it will be a short list ...
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07-26-2008, 07:11 PM
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#18 (permalink)
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Batman Junior
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Texanidiot: good story. Your dad's really on the ball if he's that aware of what's going on in traffic behind him. I used to teach rear crash avoidance as part of a defensive driving curriculum. Most are entirely avoidable. But most people don't pay attention to what's happening behind them.
Quote:
Originally Posted by tasdrouille
If power assist was the reason eocing is dangerous then power assist would be mandatory on all vehicles.
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Not when you consider that a manual rack has a different steering ratio than a power assisted rack. So when the assist goes away, it's harder to steer that car than the equivalent one with manual steering.
I'm obviously playing devil's advocate. I EOC in all kinds of cars, with some variation based on a vehicle's steering effort without assist.
But I'd prefer that people are fully aware of the consequences of losing assist in both steering & braking before startling themselves (and others?) because they attempt the technique in traffic without practicing it first. Unfortunately, I've read a couple of posts here and elsewhere of people doing just that.
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07-26-2008, 07:25 PM
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#19 (permalink)
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needs more cowbell
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Playing the Devils nemesis, my wife can EOC all around town and back into the garage on a power steering car with the engine off without any problem.
But yes, practice in a safe place, make sure you can still control the vehicle. You are responsible for not running into other people/things.
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07-27-2008, 06:00 AM
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#20 (permalink)
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Mr. Blue Tape
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Since I started HM, I've been more aware of my rear primarily to avoid slowing down traffic and to prevent potential tailgaters from forming. Since calibrating the SG and my MPG numbers are more realistic I've been using NICE-On more often but just not comfortable using it with company or at very high speeds. I only do it at night with next to zero traffic and on straightaways.
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