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JHotz
2005-Nov-20, 02:02 AM
Which vehicle is safer?

A large suv with four-wheel drive or the smallest sized front wheel drive?

The large suv provides more protection to occupants in the event of a collision. The larger mass of vehicle absorbs the impact and the greater vehicle height ensures that the impact will be below the head and torso. The down side is the greater weight, rear wheel drive and higher center of gravity means less responsiveness to stop and swerve to avoid and accident and you are much more likely to loose control and have a one vehicle accident. These vehicles are so unstable that a blown tire is very likely a major accident. This can be mitigated somewhat with antilock breaks and antispin for the drive wheels but since these technologies are available in small vehicles the are still far more dangerous in these ways

The small front wheel drive takes more damage in a collision. Because it is lower the occupants are more likely to be injured in the vital head and torso areas. The up side is they can stop and swerve much better. Because they have smaller dimensions they are a smaller targets as well. Front wheel only drive and a short wheelbase are far superior to rear and four-wheel drive in emergency situation. It is virtual impossible to roll these little cars unless they are hit or tripped. When you blow a tire in these cars you will probable only notice a slight pull and the sound of the flapping tire remains.

Klausnh
2005-Nov-20, 02:44 AM
You might want to read this site (http://www.k12.nf.ca/gc/Science/Physics3204/Projects2003/SlotA/ProjectA2/link20.htm) abount crumple zones. The large mass of the SUV may make them safer if they're hit, but if they hit something immovable they could me more dangerous. The design of the car is probably the most important safety factor. I can personally vouch for the importance of crumple zones. My wife and I were rear ended in her Honda while stopped at a stoplight. The car that hit us was going about 40 mph. The energy of impact was absorbed by the seats, which tipped over backwards so my wife and I were lying on our backs, and by the rear trunk, which was a few inches shorter after the accident. The passenger compartment was intact.
The old VW Beetle had one of the first energy absorbers in the front. It was the spare tire. I knew 2 people who survived head collsions in their Beetle because of that tire.

TheBlackCat
2005-Nov-20, 03:02 AM
These vehicles are so unstable that a blown tire is very likely a major accident.
May parents both have Landrover Discoveries. My mother had a blowout and didn't even realize it until she noticed the car was leaning to one side slightly. Run-flat tires have greatly reduced the danger from blowouts.

You also missed the whole point of having 4-wheel drive: in rain, ice, and snow 4-wheel-drive is a lot easier to control and a lot less likely to hydroplane or spin out than any 2-wheel-drive vehicle. Also, a blow-out will be compensated for by the other 3 wheels, while in a 2-wheel-drive car you are left with only one powered wheel. Also, higher-quality 4-wheel-drive vehicles have special differentials that will transfer power from wheels that are slipping to those that are holding, which means if one of your wheel loses traction in ice, snow, or rain the other wheels will take over and pull you throught it.

LurchGS
2005-Nov-20, 04:25 AM
ok, I'll stick my oar in here...

Properly driven, both sorts of vehicle are more than capable of rapid avoidance, either by swerving, braking, or accelerating. The problem is that the same set of reflexes don't work for both..and most people who drive SUVs (soccer moms/dads, not those who dirve them offroad) drive them as though they were sedans.

In bad weather, I see a lot more SUVs than non-SUVs in the ditch.

In the event of a collision, I'd *much* rather be in a larger vehicle. That's why we drive a Cougar, a Blazer, and a Lincoln. Not a small car in the bunch (though the Cougar could be.. considered 'mid-size')

Think about this - there's a reason most police departments don't drive Honda Civics

darkhunter
2005-Nov-20, 05:42 AM
Had a '77 Full size F150 one time got rear ended once while I was sitting still by a small sedan. I sprayed some paint on my rear bumper and the truck was fin. the car was totaled.

Durung the accident I just heard a crunch and the truck just rocked slightly....

farmerjumperdon
2005-Nov-20, 05:57 AM
There's a lot more to safety than having lots of metal around you. A smaller car with a well tuned suspension has much more of what it takes to avoid a collision. Rear wheel drive is much better for handling and performance anywhere but on ice. There are serious handling problems when the drive wheel are the steering wheels, even on snow and ice; though front wheel drive in those conditions is more forgiving for untrained drivers (which is most everybody). There is a reason the only hard-core racers with front wheel drive are ice racers; and they use some serious studs to maintain their traction.

I'm thinking of safety in terms of avoiding a collision. The key there is a nimble car with a good suspension and steering gear, and driver training.

Once you've goofed up or become the victim of someone else's goof up, then the biggest tank you could get around you is of course best.

genebujold
2005-Nov-20, 06:09 AM
Generally speaking, the more mass the better. However, other issues such as rollovers can be a factor.

tmosher
2005-Nov-20, 07:36 AM
Had a '77 Full size F150 one time got rear ended once while I was sitting still by a small sedan. I sprayed some paint on my rear bumper and the truck was fin. the car was totaled.

Durung the accident I just heard a crunch and the truck just rocked slightly....

1988 MB 300SE - almost two tons of German steel. Got rear-ended once in her and all I got was a small dent in the right-rear fender and a nick in the bumper. The other car lost the entire left fender. Pity I got rid of das Boot a couple of months ago - fine riding car but it sure loved it's gasoline fix every 400 miles.

Moose
2005-Nov-20, 02:10 PM
You also missed the whole point of having 4-wheel drive: in rain, ice, and snow 4-wheel-drive is a lot easier to control and a lot less likely to hydroplane or spin out than any 2-wheel-drive vehicle.

I have to disagree on several points here.

A large 4wd vehicle is less likely to jack up in deep snow (> 2.5 feet) than a basic midsized car (say a Corolla or equivalent). It's also got better footing from 0-10 mph on black ice. Both statements assume otherwise identical tires.

As for hydroplaning, the heavier vehicle has a slight advantage in not hydroplaning in the first place. No other factor matters except load balance and the driver keeping their wits about them.

From there, FWD, properly driven, will outperform the 4WD (again, properly driven) on all other bad weather criteria except engine-slowdown, all other factors being equal. I say this from direct experience in the very worst conditions the Maritimes has to offer.

It's not about the drive wheel, it's about the tires, and about the driver having the sense to drive for the conditions and his/her skill level.

Moose collisions are generally survivable in SUVs, and generally not survivable in cars. Cars fare badly against SUVs as well, because the SUVs tend to ride up over the car's crumple zones.

But until the very moment contact has been made, I prefer the car. Much better for avoiding the damage in the first place.

JHotz
2005-Nov-20, 06:46 PM
May parents both have Landrover Discoveries. My mother had a blowout and didn't even realize it until she noticed the car was leaning to one side slightly. Run-flat tires have greatly reduced the danger from blowouts.Interesting point. I do not have any experience with run flat tires.


You also missed the whole point of having 4-wheel drive: in rain, ice, and snow 4-wheel-drive is a lot easier to control and a lot less likely to hydroplane or spin out than any 2-wheel-drive vehicle.You are absolutely mistaken here. What makes a cars rear end come around in a spin on the ice is too much power to the rear wheels to initiate the spin and then a engine braking locks them up when you let up on the gas. Front wheel drive have completely passive rear wheels and a light rear end that virtualy never comes around. When hydroplaning occurs in front wheel only cars the front wheels loose traction and the vehicle slows there is little momentum to maintain the speed because the car is so light. Cars that have rear wheel drive will hydroplane without the driver being aware because the front tires clear the water to the rear and you just loose steering. Furthermore when the car does get out of align passive rear wheel cars recover much much better.
Also, a blow-out will be compensated for by the other 3 wheels, while in a 2-wheel-drive car you are left with only one powered wheel. Also, higher-quality 4-wheel-drive vehicles have special differentials that will transfer power from wheels that are slipping to those that are holding, which means if one of your wheel loses traction in ice, snow, or rain the other wheels will take over and pull you throught it.No slip all wheel drive is available on all vehicles types so it does not really mitigate the greater danger of SUV.

JHotz
2005-Nov-20, 06:54 PM
ok, I'll stick my oar in here...

Properly driven, both sorts of vehicle are more than capable of rapid avoidance, either by swerving, braking, or accelerating. The problem is that the same set of reflexes don't work for both..and most people who drive SUVs (soccer moms/dads, not those who dirve them offroad) drive them as though they were sedans.If you mean to imply that an SUV is anywhere near as agile as a small front wheel drive you are flat out wrong. Just the larger size and wheelbase length make that impossible let alone the massive weight, high center of gravity and giant tires.


In bad weather, I see a lot more SUVs than non-SUVs in the ditch.

In the event of a collision, I'd *much* rather be in a larger vehicle. That's why we drive a Cougar, a Blazer, and a Lincoln. Not a small car in the bunch (though the Cougar could be.. considered 'mid-size')Yes it is really a tradeoff between not getting in a collision and being able to avoid one. I would rather be able to avoid one.


Think about this - there's a reason most police departments don't drive Honda CivicsThey claim they need the large vehicle to hold all the equipment, their gear, and prisoners as well as have the high speed stability and durability to chase suspects as not be run off the road by hostile vehicles. These requirements are completely different from most peoples need.

JHotz
2005-Nov-20, 06:56 PM
Had a '77 Full size F150 one time got rear ended once while I was sitting still by a small sedan. I sprayed some paint on my rear bumper and the truck was fin. the car was totaled.

Durung the accident I just heard a crunch and the truck just rocked slightly....Trucks handle even worse than SUV

JHotz
2005-Nov-20, 06:58 PM
There's a lot more to safety than having lots of metal around you. A smaller car with a well tuned suspension has much more of what it takes to avoid a collision. Rear wheel drive is much better for handling and performance anywhere but on ice. There are serious handling problems when the drive wheel are the steering wheels, even on snow and ice; though front wheel drive in those conditions is more forgiving for untrained drivers (which is most everybody). There is a reason the only hard-core racers with front wheel drive are ice racers; and they use some serious studs to maintain their traction.

I'm thinking of safety in terms of avoiding a collision. The key there is a nimble car with a good suspension and steering gear, and driver training.

Once you've goofed up or become the victim of someone else's goof up, then the biggest tank you could get around you is of course best.In a race drivers will deliberatly spin the rear wheels. Not much use for this kind of performance on the street though.

TheBlackCat
2005-Nov-20, 07:15 PM
Yes it is really a tradeoff between not getting in a collision and being able to avoid one. I would rather be able to avoid one.
You can't always avoid one. Sometimes there is no way out. When that happens, I would prefer to be in a sturdier car. Especially with so many other SUV's out there, if someone is going to hit me (which I have pretty much no control over) I want to be sure that other car is going to do as little damage to me as possible.

JHotz
2005-Nov-20, 07:15 PM
A large 4wd vehicle is less likely to jack up in deep snow (> 2.5 feet) than a basic midsized car (say a Corolla or equivalent). This is true
It's also got better footing from 0-10 mph on black ice. Both statements assume otherwise identical tires.I see you point but I would say more like from 0-5 mph and the critical issue is placement of the weight. Furthermore the frontwheel drive will recover from mistakes much better.


As for hydroplaning, the heavier vehicle has a slight advantage in not hydroplaning in the first place. No other factor matters except load balance and the driver keeping their wits about them.Weight is orders of magnitude less important than power to the rear wheels. The front wheel drive cannot really hydroplane because the front wheels spin as soon as hydroplaning starts and the speed drops. The type of tire tread you have is also more important that weight


From there, FWD, properly driven, will outperform the 4WD (again, properly driven) on all other bad weather criteria except engine-slowdown, all other factors being equal. I say this from direct experience in the very worst conditions the Maritimes has to offer. I agree


It's not about the drive wheel, it's about the tires, and about the driver having the sense to drive for the conditions and his/her skill level.I disagree front wheel drive cars are safer for all drives, conditions, tires and conditions. Until you are smashed by a Hummer.


Moose collisions are generally survivable in SUVs, and generally not survivable in cars. Cars fare badly against SUVs as well, because the SUVs tend to ride up over the car's crumple zones.Good point. I wonder how SUV V SUV collisions work out.


But until the very moment contact has been made, I prefer the car. Much better for avoiding the damage in the first place.I drove a towtruck in L A and I say may smashed up cars. I never saw a critical injury. Modern cars with crumple zones and airbags are extremely good at protecting occupants.

turbo-1
2005-Nov-20, 07:27 PM
But until the very moment contact has been made, I prefer the car. Much better for avoiding the damage in the first place.Agreed. My wife and I have both owned Nissan Pathfinders, and I currently own a 4WD Nissan pickup, but the best-handling vehicle we have ever had for ice and snow is her Subaru Legacy sedan. Beautiful balance, AWD with antilock brakes. It feels like it's on rails and it stops WAY better than my truck in icy conditions. Like any vehicle, the Legacy can lose traction if you drive too fast in snow, especially the viscous slushy stuff. Use common sense (and some agressive snow tires with studs) and that little car will get you home in any weather you're likely to encounter in New England.

farmerjumperdon
2005-Nov-20, 08:00 PM
In a race drivers will deliberatly spin the rear wheels. Not much use for this kind of performance on the street though.

True, there are non-pavement racing types that intentionally spin the back wheels, but never on pavement. On pavement, as well as most other surfaces in most situations, rear-wheel is preferred for best handling overall.

Basically, I see it as 4 scenarios:

1-Pavement racing. Rear drive hands down.
2-Pavement driving on public roads. Rear drive hands down. All the same principles and reasons as in racing, just at a slower speed.
3-Loose surface racing. Rear drive again for all the same reasons, plus you can swing the back around when needed.
4-Loose surface on public roads. This is the only one where I could see a case for front-wheel. Better traction in a straight line, easier to pull thru snow than push thru, and it's really easy to do those Rockford turns. But their are tradeoffs to having the drive wheels be the steering wheels. And again, I am not aware of any serious racing (the upper classes of anything but ice racing), where front drive is preferred.

I'm not being a snob by saying certain driving isn't serious. I'm thinking along the lines of "What's the pinnacle of each type of driving?" On pavement it is probably Formula I. No way no how will you see front wheel drive there. And the reasons it does not work are the same reasons it is inferior on the street.

One other thing. The fishtail effect of most rear drive cars is actually built in because manufacturers, in the name of safety, design cars to understeer. So what happens is the front wheels drift (not slide) more than the back wheels. If a driver is going to fast for the corner and the car starts to plow, the usual reaction is to crank in more turn resulting in the back sliding around (terminal oversteer). I think they consider this a safer result than continuing to plow thru the corner or into oncoming traffic. It is safer to build cars with built-in understeer for the masses.

BTW, I had a 1972 Firebird, a model of the style of car notorious for fish-tailing, that with proper modification, would not fishtail on pavement no matter what you did.

Moose
2005-Nov-20, 08:52 PM
The front wheel drive cannot really hydroplane because the front wheels spin as soon as hydroplaning starts and the speed drops.

I assure you that this is not true. It might be a fair statement to say that a FWD cannot accelerate into a hydroplane situation, but FWDs will hydroplane when hitting water/slush just like any other vehicle.

This second scenario is the one that kills the insufficiently prepared. Not the first.

LurchGS
2005-Nov-20, 09:27 PM
The whole point here is that each vehicle must be driven appropriately for the conditions and driver experience. Given that, the liklihood of needing to perform sudden automotive gymnastics is negligible.

Having been in a few accidents (half of which occured while I was at a stand-still - completely negating any nimbleness issue), I base my vehicle choice on experience.

police may SAY large vehicles are for toting tools/prisoners - but realistically, any vehicle would do for that. The equipment load is not all that great that it won't fit in just about any random vehicle. In recent years, the larger vehicle provides much better protection for the officer inside - and allows for tactical maneuvers not possible in something like a Civic.

The comment about FWD and hydroplaning is largely correct. Given that the drive wheels are no longer in contact with the pavement, the vehicle WILL slow and cease to plane. Of course, as soon as the wheels touch the pavement again, the vehicle can accelerate again...

Enzp
2005-Nov-20, 09:40 PM
That is indeed the whole point, the driver is the critical element. Sure, I can be sitting there minding my own business when someone careens through a red light right into me, but that is not the common scenario.

Every year when the first snow hits here in Michigan, the ditches are full of SUVs more than anything. I don't think it is hte SUV per se, but instead it is the attitude on the part of the SUV driver that his four wheel drive is invulnerable.

I have been driving in Michigan the last forty some years, and we have our share of snow and ice. I have always maintained that good driving technique will keep me out of trouble better than hardware.

And a manual transmission with clutch please. If I find myself nosed into a drift or stuck on an ice ridge, it is far easier to rock it free with a clutch than with an automatic.

TheBlackCat
2005-Nov-20, 10:03 PM
That is indeed the whole point, the driver is the critical element. Sure, I can be sitting there minding my own business when someone careens through a red light right into me, but that is not the common scenario.
Actually, according to an insurance agent I know rear-end collisions are by far the most common type of accident, at least in my area. If you are in a rear-end collision, an SUV's sturdier construction and higher mass will give you a distinct advantage.

Moose
2005-Nov-20, 10:29 PM
TBC, I would suggest that the SUV's greater mass and stopping distance would increase the likelyhood of being the cause of that hypothetical rear-end collision.

LurchGS
2005-Nov-20, 10:38 PM
TBC, I would suggest that the SUV's greater mass and stopping distance would increase the likelyhood of being the cause of that hypothetical rear-end collision.

tsk - it's been demonstrably proven in a number of studies that any given vehicle almost *never* is the cause of a car crash. It's almost always the result of the actions of the driver.

(sorry, just had to tease a bit)

But, to address the point, the mass and stopping distance is pretty meaningless here - rear-enders are caused by people driving improperly. Stopping distance only comes into play when the driver recognises there is a problem in sufficient time to do something about it.

Gillianren
2005-Nov-20, 10:49 PM
Re: hydroplaning:

Many years ago, at one of the high schools in my home town, a student took advantage of a rare rainy day to play a prank. Since schools down there are not designed for rainy days, there are invariably huge puddles in front of most of the outer doors--both outside and inside them. Said student poured oil (vegetable, I believe, but I heard this story over ten years ago) onto one of the puddles.

The driver's ed teacher from whom I heard this story told it as an example of why hydroplaning was so nasty down there--it seldom rains, so when it does, all the oil on the surface of the road rises to the surface of the puddles, making the whole thing even slicker. Apparently, people (who have no wheels at all) were hydroplaning down the hall from crossing that puddle.

DOOMMaster
2005-Nov-22, 05:25 AM
You want the best car for an accident? There really isn't any such thing. Of course, the best bet is to avoid the accident in the first place. But if you get into an accident, it's going to depend on what type of accident. For example, a frontal collision with a moving car, your best bet is going to be something big that is going to absorb the impact rather than you. Same thing if you are sitting still and another car runs into you. This is why people think they feel so safe in big trucks, SUVs, and sedans.

But change the accident to something like a rollover and your big SUV is a liability, not an advantage. You want a small, lighter weight, low car for maximum survivability. Of course, your small car is also much less likely to rollover than a big SUV due to the lower center of gravity, so the likelihood of rolling over is very low anyway.

As for the differences in what wheels are best to drive, it's always going to be rear wheel drive, period. Unless you are rock climbing, mudding off-road, or other severely traction limited terrain off-road, you don't need 4 wheel drive. All-wheel drive is a overweight and wasteful (most all-wheel drive systems add about 300 pounds and suffer drivetrain losses of over 40%) solution to people not learning how to properly drive a rear wheel drive car. Front wheel drive is NOT better than rear wheel drive in low traction environments, it's actually worse. The only advantage front wheel drive offers is the fact that it puts more weight on the drive wheels for starting off in low traction (this can be solved with rear wheel drive by adding weight over them, such as sandbags or weights in the back of the vehicle). If you know how to properly drive rear wheel drive you will ALWAYS be able to outdrive and outmanuever anyone driving a front wheel drive car in a low traction environment.

Don't believe me? Feel free to come to Central Illinois this winter when it gets nasty. I'll be driving my rear wheel drive Camaro Z28 like I do every year, having a good laugh at all the front and 4 wheel drive cars off in the ditch because instead of learning how to drive properly, they bought a car thinking it's drivetrain would do it for them.

beskeptical
2005-Nov-22, 08:46 AM
Use the evidence, the crash tests and the accident statistics. It is not scientific to just ask your friends' opinions. :D

Fram
2005-Nov-22, 10:05 AM
Actually, according to an insurance agent I know rear-end collisions are by far the most common type of accident, at least in my area. If you are in a rear-end collision, an SUV's sturdier construction and higher mass will give you a distinct advantage.

I'm just using this post as an example, similar points have been made by different people here.
From the by me emphasised bit: this is true, if you are the one in the SUV. Which one would you prefer rearending you, a SUV or a small car?
What I mean is this: the extra safety you perhaps get by driving a SUV is an extra loss of safety to other people not driving one.
There are studies (but I don't have them available right now) that also show that a pedestrian hit by a SUV is worse off than a pedestrian hit by a small car (at the same speed of course). In this regard, the SUV is unsafer.

enginelessjohn
2005-Nov-22, 12:06 PM
Wow, so little understanding of front wheel drive.

First up hydroplaning. I've done this in both front and rear wheel drive cars. And the first thing you do when hydroplaning is to GET YOUR FEET OFF THE CONTROLS. Any car will loose traction in this situation, and franky it's academic which wheels are supplying power when hydroplaning as Mr Newton is doing the driving.

Does it matter which set wheels are being driven? No. (IMHO) If you think that your rear wheel drive car will give you the edge in performance, what on earth are you doing driving like that on a public road? And more important than which set of wheels are driven is how the suspension is set up.

An example(anecdotal, but bear with me).... A couple of weeks back I was in the US on a business trip, and it involved a fair bit of driving around. The rental car was a Chevrolet Impala. My own car here is a Saab 9000, which also gets classed as a "large car" by the EPA. Both are front wheel drive, although my car has a manual gearbox as opposed to an automatic. Now going over a flyover onto a freeway in the dry (i.e. a good fast bend) the Impala would wallow all over the road at 55 mph and felt deeply uncomfortable. By comparison I routinely go around similar bends in the Saab in excess of 65 mph happy in the knowlege I've got huge amounts of margin if I need to correct and adjust. If I had to avoid an accident I know what I'd want to be in....

Front wheel drive cars do tend to understeer, until the power is backed off, at which point they will oversteer. Rear wheel drive cars if correctly set up should be fairly neutral until oversteer when removing the power should correct things.

As to needing to ballast a rear wheel drive car, this means extra fuel from lugging around all the extra weight. And as for a "low traction environment" accelerating isn't the problem, stopping is. Front, rear or four wheel drive won't help you there.

SUVs and accidents.... Well the most balanced I could find was

http://www.stats.org/record.jsp?type=news&ID=388

Which has an interesting take on things. Especially on driver attitudes....

Other things to think about. In a rear end collision you need a crumple zone to absord the energy of the car behind to minimise whiplash to your neck. In a vehicle with a solid chassis (an SUV) this energy will be transferred directly to you.

The upshot is that for any car you own you should find a nice empty car park in the wet/snow/ice and learn how your car behaves when it looses grip. Every vehicle I've owned I've done this with, and it has saved me from an insurance claim on several occasions. I've even drifted my VW campervan...

Cheers
John

Moose
2005-Nov-22, 12:32 PM
Don't believe me? Feel free to come to Central Illinois this winter when it gets nasty. I'll be driving my rear wheel drive Camaro Z28 like I do every year, having a good laugh at all the front and 4 wheel drive cars off in the ditch because instead of learning how to drive properly, they bought a car thinking it's drivetrain would do it for them.

I'd take that challenge. You with your Camaro, me with my nice, sedate Corolla (although my previous car, a Topaz, was far more capable in the snow for some reason, assuming I could start the thing.)

Only come to New Brunswick on a real storm day before the plows have had much of a chance to clean up. We'll go play on the tertiary roads. Odds are you'd jack up before you made it out the driveway, but I can show you the real advantages of FWD in snow country for those who know how to drive one sensibly.

Otherwise, I have no doubt there are stunts you can pull with a RWD that you can't on FWD. If you value that sort of thing, more power to you.

Moose
2005-Nov-22, 12:40 PM
And as for a "low traction environment" accelerating isn't the problem, stopping is. Front, rear or four wheel drive won't help you there.

Well said, overall, but this is not quite right.

If you decelerate by downshifting, AWD (and to a lesser degree 4WD) will apply drag more evenly than either 2WD models. This matters mostly for that half-second after releasing the clutch when in bad footing (slush especially), after which the point is largely moot.

The tradeoff is the extra weight which will tend to lengthen the stopping distance.

farmerjumperdon
2005-Nov-22, 02:33 PM
Definitely agree that the biggest factor in safe driving is the driver. Especially when driving at speeds appropriate for conditions (and no more than the posted limits), most cars are capable of delivering a person safely to their destination - as long as the vehicle hasn't been severely modified in a negative manner (such as jacking up the rear end and stuff like that).

High-end or high-tech gear and modifications aren't necessary unless a person is pushing the limits.

genebujold
2005-Nov-22, 09:21 PM
Me? Well, huh, I drive an ASTRO. It's 104 tons of pure fossil-fuel guzzling Americana, man. I've got my house, two extra cars, my 14,250 Watt 7.1 entertainment center, a jacuzzi, my lap lane, and a small suite for the mother in law. I've even got a seventh bedroom that doubles as a suite for additional inlaws and guests, or even a mobile office, but that's usually used by my lawyer. I'm not much into office work.

It's cool beans, brother!

Twice I've hit other cars and never even knew it until I hit the state line.

Thank gawd my mother in law still has her license. She's pushin' 80, but she's got as much "getheheckoutofmyway!" as her grand kids!" Huh-chucka-chucka-guffsnicka...

Hey! Betty Joe? Can you get me another? Thanks, honey.

LurchGS
2005-Nov-22, 10:51 PM
Definitely agree that the biggest factor in safe driving is the driver. Especially when driving at speeds appropriate for conditions (and no more than the posted limits), most cars are capable of delivering a person safely to their destination - as long as the vehicle hasn't been severely modified in a negative manner (such as jacking up the rear end and stuff like that).

High-end or high-tech gear and modifications aren't necessary unless a person is pushing the limits.

I'm not one who normally espouses lawbreaking, but 'driving no more than the posted limits' is foolhardy. You should travel at the same (approximate) speed as most of the people on the highway - no matter what the posted limits are. The groups to avoid are the fastest 15% and the slowest 15% - those are the dangerous people on the highway (according to the NTSB and NHTSA) (oh, I may be off a little on those percentages, but it's in that range)

If you feel you can't travel at that velocity, it's time to get off that road and onto another.

DOOMMaster
2005-Nov-23, 03:55 AM
I'd take that challenge. You with your Camaro, me with my nice, sedate Corolla (although my previous car, a Topaz, was far more capable in the snow for some reason, assuming I could start the thing.)

Only come to New Brunswick on a real storm day before the plows have had much of a chance to clean up. We'll go play on the tertiary roads. Odds are you'd jack up before you made it out the driveway, but I can show you the real advantages of FWD in snow country for those who know how to drive one sensibly.

Otherwise, I have no doubt there are stunts you can pull with a RWD that you can't on FWD. If you value that sort of thing, more power to you.

I used to live out in the middle of nowhere and they didn't plow the roads for days. As long as the snow isn't too high to stop the car (which on a Camaro is going to be a few inches lower than your Corolla, so you can still get through some snow that my Camaro wouldn't, but that has nothing to do with front wheel drive, it has to do with clearance), you'll lose every time. The perfect example would be a car of similar weight and size of your Corolla, as well as the same riding height, with the same tires. It's about knowing how to drive the car and avoid getting into a situation that might cause an accident. And if something happens (such as hitting a patch of black ice you can't see and causing a loss of traction), knowing how to get out of it.

TheBlackCat
2005-Nov-23, 04:08 AM
I'm not one who normally espouses lawbreaking, but 'driving no more than the posted limits' is foolhardy. You should travel at the same (approximate) speed as most of the people on the highway - no matter what the posted limits are. The groups to avoid are the fastest 15% and the slowest 15% - those are the dangerous people on the highway (according to the NTSB and NHTSA) (oh, I may be off a little on those percentages, but it's in that range)

If you feel you can't travel at that velocity, it's time to get off that road and onto another.

I do not agree with that. The speed limits, at least in the US, are not arbitrary. The roads are designed to be safe for cars travelling at a certain speed. Ever notice how the interstates bank at sharp turns? That is because engineers calculated what turns cars could handle under various weather conditions with the various angled roads given the paramaters of the cars and the traction of the road under those conditions. That is what the speed limits are there for, and that is why they give tickets for people who ignore them. If everybody else is doing something dangerous and foolhardy, that is no reason for you to do the same. Even if you only get a ticket, it will significantly impact your insurance rates. And no, the fact that everyone else was speeding is not a valid defense to the cops or a judge. In most states you are legally safe if you are going up to five miles an hour over the speed limit (but check your local laws). At least in the state I used to live in it was illegal to go over the speed limit, but there wasn't actually a ticket category for 1-5 mph over so you couldn't legally get a ticket for it. However, that is assuming the police will ticket you for the right speed. In some areas where that law applies, the cops will simply jack up your speed 5mph on the ticket so they can fine you. In those areas, such as rural areas of non-interstate highway, you should never even go the speed limit. I usually go 2-3 mph over on local roads, and about 4-4.5 mph over on interstates. I was told by a highway patrol officer that on interstates you are safe up to about 8 over, but over that you are going to get a ticket (I was not driving, but the person who was had been going 90). And even so that was just one patrolman's take on it from one state. Local roads are another matter entirely, there you want to stay within legal limits, or even below them if you are in an area with notoriously stringent cops.

JohnD
2005-Nov-23, 08:57 AM
Threadhijack:

Earlier on, Tmosher contributed. They have a tag/signature to the effect that the "Average IQ of people in the US is 98" Hmmmmmmm.

You don't need to be very intelligent to know that IQ is a comparitive (and very crude) measurement of intellectual ability. Comparitive, in that by the definition of "IQ", the average in a population is 100. 98 is well within sampling error.

JOhn

farmerjumperdon
2005-Nov-23, 03:36 PM
[QUOTE=enginelessjohn]Does it matter which set wheels are being driven? No. (IMHO) If you think that your rear wheel drive car will give you the edge in performance, what on earth are you doing driving like that on a public road? And more important than which set of wheels are driven is how the suspension is set up.

Front wheel drive cars do tend to understeer, until the power is backed off, at which point they will oversteer. Rear wheel drive cars if correctly set up should be fairly neutral until oversteer when removing the power should correct things.

The upshot is that for any car you own you should find a nice empty car park in the wet/snow/ice and learn how your car behaves when it looses grip. Every vehicle I've owned I've done this with, and it has saved me from an insurance claim on several occasions. I've even drifted my VW campervan.../QUOTE]

Wasn't sure if you meant in general or for one of the certain specific situations mentioned - but in handling overall, it absolutely matters whether or not the drive wheels are also the steering wheels. To make matters even more complicated, the front tires also provide the bulk of the stopping power (unless you are braking while moving in reverse).

Almost all cars oversteer as set up by the factory. All cars, not just rear drive, if correctly set up should be nuetral. A simple test to see how the car is set up is to find a big open space and drive in a circle, slowly and without changing the steering input at all once you start moving. When the circle is complete, if the car angles in towards the center of the circle you just scribed, the car is set up to oversteer. If it angles out from the circle, the car is set up to understeer. (It doesn't matter if you ended up farther out, that is the product of drift).

You mentioned drift in the VW van as if that were difficult. All cars drift at any speed if they are moving in anything but a perfectly straight line. Drift is the result of tire flex and is not synonymous with sliding or loss of adhesion. Drifting and loss of adhesion (sliding) are 2 very different things in car handling lingo. Unless the tires are made of solid steel, all cars will drift whenever they are turning.

I definitely agree with taking the car to an open lot and experimenting. Most people's 1st experience with loss of control is in an emergency. Such a horrible way to learn. I've taught several people to drive, and the 1st thing I do is take them to an open lot and make them lose control. Everyone should know the performance limits of their car, what it feels like just before you hit them, how to manuever at that edge, and how to get control back if it is lost. I often wonder how many people have died because their 1st experience at the edge of control was their last.

It's not that I advocate using the public roadways as a race track. But those are the conditions (a manuever performed at higher than usual speeds) a person will encounter in an emergency, and it is good to have practiced those skills before you actually need to use them in a real emergency for the 1st time.

Speed is the only reason handling is a concern. Whether it is because more speed is desired or because a person is forced to perform a manuever at higher speeds than they usually would because of an emergency doesn't matter. If everyone drove 10 MPH everywhere all the time, it would not matter what was being driven or how it was set up. At 10 MPH, a moped can handle switchbacks or an emergency stop as well as a Maserati. The only reason we pursue handling is because we desire more speed, or are forced to perform at higher speeds in an emergency. I only make the point (and possibly belabor it - sorry), because I seem to draw coments like 'Why do you drive like that?' on a regular basis. I don't drive 'like that' on a regular basis; but am extremely skilled at driving 'like that' when it is needed.

Just as an anecdote; I've been giving my 8 year old driving lessons for 2 years already. She just steers the car so far, but she is getting serious time behind the wheel. When we go-kart she drives solo and beats everybody because she already knows how to drive a line and negotiate corners. With that and her very low weight - nobody can beat her.

gethen
2005-Nov-23, 03:44 PM
I assure you that this is not true. It might be a fair statement to say that a FWD cannot accelerate into a hydroplane situation, but FWDs will hydroplane when hitting water/slush just like any other vehicle.

Absolutely. Been there. Hit a patch of relatively deep water during a light rain at night and went for an unplanned slide. I didn't think I'd been driving very fast at all, but apparently it was too fast for conditions. So I'd consider it driver error.
I'm also driving a Corolla now, with the side curtain airbags added for safety's sake, and I find the steering to be way more responsive than that of my husband 4wd pickup. I hate driving that thing. Turn the wheel and wait for a response. It has its uses, but driving in congested fast moving traffic is not one of them.

Nicholas_Bostaph
2005-Nov-23, 06:09 PM
The speed limits, at least in the US, are not arbitrary. The roads are designed to be safe for cars travelling at a certain speed. Ever notice how the interstates bank at sharp turns? That is because engineers calculated what turns cars could handle under various weather conditions with the various angled roads given the paramaters of the cars and the traction of the road under those conditions.

Not to stray from the OP, but...

You're correct, the speed limits aren't arbitrary. However, I disagree that travelling over the speed limit is automatically 'dangerous'. You said that the roads are designed based on specifications of cars under certain conditions. My question would be: what cars? A Ferrari can drive more safely, even if travelling at a much faster speed, than my Firehawk. Likewise, I'd say my car is much safer, even at a higher speed, than an overbearing SUV. Then, of course, there are the differences in the skill levels and response times of the respective drivers. The variations are not insignificant; I've seen many drivers that I trust much more at 50 than I do the average driver in an average car at 35.

The fact is, there is no single limit that can be imposed where every driver in every car driving under that limit is safe and every driver in every car driving over that limit is unsafe. A more accurate form of controlling safety may be to assign an A-F classification for each car and driver, based on regular tests, that are stored in a small transmitter within each car. The RADAR gun could read that digital information at the same time it's gauging speed to determine if someone is driving over their personal limit in that vehicle. I doubt we will see that anytime soon, though, as my personal feelings are that speed limits are not about safety.

In the US (I think, but it may just be PA) all residential zones are automatically 25 mph. However, not all residential zones have many residences on them, and many are perfectly straight roads in optimal condition. Why, then, is travelling at 28 on this straightaway dangerous, while travelling 34 on a twisty back road is not? I would contest that speed limits are more politically motivated, and way too overgeneralized to be any good. Several times in the past I've almost lost control while travelling five under the posted limit because of road disrepair, while I could easily travel my own street at 15 over the posted limit at relatively greater safety.

Does anyone know where I could find statistics on the causes of accidents? Almost all those I have seen or heard about were the result of driver error, and did not involve speeding, but that is only anecdotal evidence. I'd be curious to see what the hard evidence says.

enginelessjohn
2005-Nov-23, 06:46 PM
Almost all cars oversteer as set up by the factory. All cars, not just rear drive, if correctly set up should be nuetral. A simple test to see how the car is set up is to find a big open space and drive in a circle, slowly and without changing the steering input at all once you start moving. When the circle is complete, if the car angles in towards the center of the circle you just scribed, the car is set up to oversteer. If it angles out from the circle, the car is set up to understeer. (It doesn't matter if you ended up farther out, that is the product of drift).


I'm not certain I'd agree with that. Googling also brought this link up:

http://www.me.umn.edu/education/courses/me5286/vehicle_dyn/Vehicle%20Dynamics%20Lecture05.pdf

Which is quite interesting, and covers most of the points specifically that most cars are set up to understeer.




because I seem to draw coments like 'Why do you drive like that?' on a regular basis. I don't drive 'like that' on a regular basis; but am extremely skilled at driving 'like that' when it is needed.


The point I was trying to make is probably best summed up by the aviation truism

"A superior pilot uses their superior judgement to avoid having to use their superior skills"

I'm not making any claims for my own driving here...

As to the speed thing, there is a school of thought that defines the safest speed to be going at the 85th percentile speed of the mean distribution. I'm not going to provide a link as I can't find anything that doesn't appear to be labouring a point. Anyway my understanding is that if you are significantly over or under the mean speed of the traffic you increase your chances of an accident.

Of course if you happen to be going faster when you have that statistically less likely accident, you have more kinetic energy to get rid of so the outcome is potentially more serious. That said when I'm driving I do tend to try and keep up with the traffic, which is no mean feat in an old VW.... :)

Cheers
John

LurchGS
2005-Nov-23, 10:08 PM
I do not agree with that. The speed limits, at least in the US, are not arbitrary.


I never said they were. I pointed out that it's *safest* to be driving at the same spead as the majority of the other drivers on the road - if you are on the interstate and maintaining the posted speed of 55, while 80% of the other cars on your side of the road are doing 75, you are creating a hazard, and in most states area actually liable for a ticket while those passing you are not.

On the other side of the coin - if you are driving right on the posted limit and everybody else is driving 10-20 miles BELOW it, you are again posing a hazard and are liable for the ticket.

if you are all by your self, then by all means, stick to the posted limit.

In every state I've been in, so long as you travel at the same speed as the majority, you will never receive a ticket (other circumstances excepted).

Nicholas - while technically a pretty neet idea, transponders won't really make a difference in this regard - it's not about 'how safe is this car on this highway at that speed?', it's about the relative speeds between the vehicles sharing the road.

As far as getting that data, I'd ask NTSB and NHTSA

genebujold
2005-Nov-23, 11:09 PM
I'm not one who normally espouses lawbreaking, but 'driving no more than the posted limits' is foolhardy. You should travel at the same (approximate) speed as most of the people on the highway - no matter what the posted limits are. The groups to avoid are the fastest 15% and the slowest 15% - those are the dangerous people on the highway (according to the NTSB and NHTSA) (oh, I may be off a little on those percentages, but it's in that range)

If you feel you can't travel at that velocity, it's time to get off that road and onto another.

That's why I love the autobahn, LurchGS. There are posted speed limits where there need to be posted speed limits, and unlimited zones where speed really isn't a factor (unless you're a horrible driver).

I usually cruise around 100 mph from one place to another, as high as 130 when able, and back down to 83 mph when the autobahn's mandatory 130 kph kicks in through the more curvy stretches.

It'd sure be nice if the U.S. adopted this system. It just works.

At least over here.

LurchGS
2005-Nov-23, 11:17 PM
well, I admit it would be fun...

I will admit I hit 120+ on the interstate between here (my office) and home a couple years ago (long-ish story - suffice to say the day care people sent my kids home without warning or reason). I didnt' intentionally speed - but I looked down at the speedometer when I was .75 of the way there and the needle was burried. Good thing the interstate was almost empty.

I don't know if the German system would work on our autobahn - different mindset of people, and a much larger system over all. I think Montanna tried it for a year or so not too long ago - from what I hear, it got really messy.

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if you see me pass you, I'm not going fast enough