I can't tell in normal driving. As AE says, start pressing on and it's pretty obvious. Accelerating hard in a low gear on a bumpy road, or giving it beans in a corner/roundabout with lock still on will show it up quite quickly.
Cheers
DP
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We live in very hilly country: half way up a 300 meter high hill.
In summer spring autumn and most of winter no problems., A yoga acquaintances' BMW 520i was absolutley fine.. as is my Yaris/Fiesta/106 various other people's fwd..
But in snow and ice, I carry on slowly, she stops and walks.
Unless you put on winter tyres - pretty pointless for 3 weeks a year, rwd = undriveable in snow and ice..
I say no more..
And yes you can tell .... in rwd you see the bit of the road you have just come from as you spin 180 degrees on ice..:-)
RWD is for people who live on the flat or Southern ENgland..
Edited by madf on 26/08/2008 at 17:03
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>>RWD is for people who live on the flat or Southern ENgland..
Hmphhh!!!
Folks that learned to drive in RWD cars back in the sixties and seventies, learnt HOW to handle a car, and drive it properly, especially if it was on crossply tires (as previously discussed in other threads).
The trouble is nowadays, that "most" cars are FWD, with the more powerfull marques on RWD. A lot of people today that learnt to drive FWD think they can just jump in a RWD and use it exactly the same! they can't! it's a different style of driving altogether. This fact is often mentioned in this forum by people saying they find RWD scary, unpredictable, etc, this is nonsense its simply down to the fact they haven't adjusted thier driving style to suiit.
I think we were simply better drivers back then! and RWD is suitable for us Northerers too! Why should you Southerers have all the fun? ;-)
Billy (Who's 8 out of 10 cars were RWD)
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RWD is for people who live on the flat or Southern ENgland..
Which will be why most BMW's are RWD, BMW being located in Bavaria which has the highest mountain in Germany (Zugspitze)
Edited by gmac on 27/08/2008 at 00:09
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Certainly my 'normal driving' will very soon tell me which end of the car is driven. But then I already know, from the moment I set eyes on the car or am told what it is. I would have thought that would apply to a majority here.
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in truth lud is right. I know before getting the keys which is which. Hard to be objective really
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All modern cars understeer.
If you over accelerate in a RWD car, it's the back wheels that lose grip, and it's the back end that comes round on a corner - but, this isn't what I would call oversteer. It's just an over acceleration skid.
Same in a FWD car, if you over accelerate, it's the front wheels that lose grip, and the front end that drifts wide. Again, an over acceleration skid, but, not understeer.
So fundamental, it deserves frequent repetition - Under neutral conditions all modern cars understeer.
In normal use, and if the car is well engineered, you won't feel the difference. Torque steer can, to a great extent, be eliminated by good driveshaft/suspension geometry. It's only when a driver has pushed the car too far (on the public roads) that there's a discerible difference.
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Anytime the back comes round regardless of how its caused is oversteer.
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Quite AE. I remember my Arna with some affection for the beautiful way it oversteered even under acceleration on some bumpy wet roundabouts, the only genuine FWD oversteerer I have come across.
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Quite AE. I remember my Arna with some affection for the beautiful way it oversteered even under acceleration on some bumpy wet roundabouts the only genuine FWD oversteerer I have come across.
That was due the front and back being connected by flexible lacework iron oxide.
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That was due the front and back being connected by flexible lacework iron oxide.
Quite true AE actually, but not very rusty, just jelly-like in basic design. No anti-roll bars at either end, but quite pronounced negative camber on the rear suspension in a vain attempt to compensate for the floppy monocoque... most amusing motor, not much class except in the engine department but willing and fun.
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Anytime the back comes round regardless of how its caused is oversteer.
No.
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yes>> >> Anytime the back comes round regardless of how its caused is oversteer. No.
yes
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No!
In popular parlance, you are right.
But, popular parlance and usage, and most importantly the rantings of idiots like Jeremy Clarkson is wrong. Badly wrong.
The relevant standard; SAE J670e, Vehicle Dynamics Terminology; defines oversteer and understeer purely in terms of steady state behaviour.
The full definition is very tedious, but, completely steady state. When you are accelerating, braking, changing the steer angle, when the camber is changing, etc, etc, that is no longer steady state, and so falls outside of the definition - i.e., it's another effect, and isn't purely oversteer or understeer anymore.
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The full definition is very tedious but completely steady state.
But hustling a car past its first youth round a succession of bumpy bends can, for a variety of reasons, reveal another side to its character, however theoretically perfect in terms of steady-state progressive slight understeer the thing may have been when new. This is a case where the seat of the pants has it in spades over those hard-worked frontal lobes.
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N_C I normally find your posts fascinating, informative and educational. This one is pure smoke and mirrors tho. Of course there is "no steady state", if there was a steady state there would be no oversteer understeer or any kind of steer for that matter.
Its a very simple theory. If the front tries to go straight on when you try and point it somewhere else its understeer. If the back starts to come round pointing the nose anywhere other than where you wanted it, its over steer. If the whole lot is doing a combination of those two (which means the whole lot is sliding sideways in some degree or other) its "drifting"
They are by definition, purley generic terms, that amply desribe the behaviour the driver is seeing and thus universly understood as terms by those who need to know. The simple driver.
As generic terms in everyday use they are what they are, despite what you may wish.
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>>This one is pure smoke and mirrors tho.
No, it's the definition, accepted and used by the vehicle dynamics community.
It's perfectly possible for understeer or oversteer to occur in steady state - in fact, they could continue until the car's fuel ran out! It's becuase you're holding onto the wrong definition of overteer and understeer that you're having difficulty. There's no need for a car to be skidding in a gross sense to be oversteering, or understeering.
>>It's a very simple theory.
Yes, but it's one that most, including you simply get wrong. Consistently and frequently wrong.
The events you describe is more nearly described as an over-acceleration skid.
>>despite what you may wish.
It's nothing to do with what I may wish - it's how they are defined. I can no more argue with it than you can.
(I knew that as soon as posted the reference to the applicable standard, that a post would return saying that AE knew more than the SAE!)
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You dont grasp it do you NC - it centres on the term MOST. When MOST understand a definition in every day language and use then it is true, This is language we are talking about inot an ivory tower scientific view, which is this situation is simply not relevant.
I defy you to have any car on the road in real life driven by a real driver to have Steady state.
Oversteer is is oversteer as we understand it. I am not disputing the SAE standard just that it has simply no relevance in this argument.
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NC, can you post a link to these SAE standards?
Like RF I cant see how understeer or oversteer can be present in a steady state or defined as 'steady state'
Rather understeer and oversteer simply describe the reaction of the vehicle to the driver's selected steering input.
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>>When MOST understand a definition in every day language and use then it is true
No. No a thousand, no a million times. When you say oversteer, you are using a technical term, like it or not; when using any technical term, the definition is important.
If, on the other hand, people simply referred to "losing the back end", I would have no qualm. It's the mis-use of the technical term that is simply wrong.
>>I defy you to have any car on the road in real life driven by a real driver to have Steady state.
Now you're the one using smoke and mirrors. Like DC, steady state doesn't really exist, but, sufficiently close to it does.
One realistic way to test a car is to drive slowly round a painted circle of known size, taking note of the steer angle. Very slowly, the car's speed is increased, and the steer angle re-measured. By taking the radius of the circle, and the speed versus steer angle data, you can begin to assess a car's characteristics. Done carefully, this is sufficiently close to steady state.
People with the back end of their cars flying out because they were clumsy and applied too much throttle aren't anywhere near steady state - they are over acceleration skids.
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People with the back end of their cars flying out because they were clumsy and applied too much throttle aren't anywhere near steady state - they are over acceleration skids.
What about lift-off "oversteer" which can also provoke a rear end slide just through a gentle forwards transfer of weight on the limit (presumably the slight unloading of the rear tyres and changes in suspension geometry as the rear suspension extends slightly play a part)
I'm not arguing with you NC, just curious. I always took these terms at face value, because you even hear the top level engineers and designers in F1 and other motorsports talking about oversteer and understeer in the "popular" sense of the words.
Cheers
DP
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>>What about lift-off "oversteer"
A rear wheel skid, provoked by forward weight transfer.
>>because you even hear the top level engineers and designers...
Yes, I am making a pedantic point, and yes, I am swimming against the tide (not for the first time, and, hopefully, not for the last!). My point remains that the terms under- and oversteer are very tightly defined in the SAE documents, and widely mis-used.
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>When you say oversteer, you are using a technical term, like it or not; when using any >technical term, the definition is important.
N_C. in this instant, under these cicumstances, really it isnt. you are merely complicating something easily understood for no better reasoin than it does not fit into an ordered engineers mind.
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>>N_C. in this instant, under these cicumstances, really it isnt.
OK, here's the sentence you wrote which originally caused my intemperate reaction.
Anytime the back comes round regardless of how its caused is oversteer.
You were attempting to re-define oversteer, and I have been saying that a more authoritative and correct definition already exists in the SAE standard. (Which, as you have to buy it from SAE isn't freely available online).
I'm sure you will continue using the word to mean exactly the same as you've always thought it meant, and I'll continue to use it in its more restricted, more useful, correct sense.
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thats point N_C
on here and under these circumstances your SAE meaning has NO sense! In the real world, when driving (not inyour lab) when the back comes round and points the car nose tighter than i want its oversteer, I dont goive a hoot about your SAE standrd because it has no bearing on my current moment of panic. Its oversteer.
I shall leave it at that.,
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driver has pushed the car too far (on the public roads) that there's a discerible difference.
Seeking at least the safe inner non-ragged edges of a car's handling limits by 'pushing it too far' is in fact normal driving for me, and I would have thought several others here. But what do I know? I wouldn't want to encourage anyone who hasn't always done it to start now though.
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Dashboard vibrates when accelerating from a junction.
You feel a tug at the steering wheel under acceleration.
These are just two of the reasons why Front Wheel Drive is for learner drivers, small town cars, and cars built on the cheap.
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These are just two of the reasons why Front Wheel Drive is for learner drivers small town cars and cars built on the cheap.
Are you serious with this Bavarian sunshine blowing?
DP
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Michael, out of interest, what car do you drive?
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Michael out of interest what car do you drive?
A BMW 530i Sport.
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>> These are just two of the reasons why Front Wheel Drive is for learner drivers >> small town cars and cars built on the cheap. Are you serious with this Bavarian sunshine blowing?
Since when were the only RWD and AWD cars made in Bavaria?
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To answer the question, yes, very quickly.
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Soon as you pull away at anything other than a snail pace, can feel the front of the FWD car lift and sag between gearchanges, unpleasant compared to a RWD, and even more so when you get a move on.
As regards this winter wonderland where only FWD cars can go, perleese, i've had RWD cars in some atrocious weather and always got through where FWD cars have failed miserably to move at all.
Had about 8 people in the back of my 245 volvo estate one very nasty winter evening, their minibus couldn't get through the foot deep snow, but my little lad was in hospital, so they all piled in the back, the extra weight enabled me to get to the hospital, and them to go home.
If things get bad you can always load up the boot, useless with FWD.
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>>can feel the front of the FWD car lift and sag between gearchanges
There's no fundamental reason why FWD and RWD cars will have any different behaviour under drive related pitch. It's more likely the case that FWD car will tend to have a shorter wheelbase, and a greater propensity to pitch.
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I'm confused?
There seems to be RWD fans on this thread but I dont know why? Whats wrong with FWD? Over cook a corner and they tighten up - thats great isnt it? I Know shorter wheelbase FWD cars can snap back a la 205.
The RWD cars I have had better, less corrupted steering and seriously good turning circles yet have been poor in snow and wet diesel spilled roundabouts.
You wouldnt thow a hammer handle first (RWD) would you?
You could argue that if you are on the ragged edge then arent you going too fast on the public road?
I'm not sufficiently skilled to exploit FWD or RWD so unless I need to do towing FWD is just fine.
Perhaps RWD is for real men?
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David, i'm a RWD fan for lots of reasons, and its certainly not because i'm some sort of hero driver, nothing could be further etc.
I like RWD to drive whatever speed i'm doing, and however i wish to progress, i nearly always have auto anyway, and the smooth constant acceleration, predictable smooth cornering and sure footed feeling makes driving so much more pleasurable.
I know there are FWD cars around that can probably outmanoeuvre and outperform most RWD (lets be honest most of us don't own AMG 6 litre monsters) cars, but if you use the performance of a FW car, the first thing you'll get is wheelspin, then torque steer and that horrible push pull effect between the gears.
Ask the RWD to do the same, especially auto and whoosh, no drama, no change in how it feels, the car just does what you ask when you ask.
If you've had poor handling RW cars in the past, may i ask if they were very old designs, which is unfair to compare to a modern FW, and i would concede that good quality tyres are probably more important on the RWD car anyway.
But then that tends to go with the type of driver you are anyway, i don't know anyone who drives a RWD car spiritedly and buys cheap tyres.
I'm not sure that i'd want a manual turbo car in RWD unless it was a reasonably heavy beasty, i for example would not want a Nissan 200 turbo, fine and fast car though they are, maybe too light on the back for me.
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I think it's a general dig at how you continually mention the wondrous nature of your E39 530i Sport and how nothing else can possibly match it. Yes BMWs drive well but they aren't the be all and end all that you'd like to make them out to be.
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Having learnt to drive in the early 60's, when all cars were RWD (ext. Mini) have now return to the fold,(Lexus IS 220d) and the difference is stunning on the roads where I live (Cumbria).
In my opinion all FWD cars are compromised.
DJ
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In my opinion all FWD cars are compromised.
why was the horse never at the back pushing the cart? The romans knew a thing or two, but you never saw a RWD chariot?
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why was the horse never at the back pushing the cart? The romans knew a thing or two but you never saw a RWD chariot?
Because that would be rear wheel steer and thats always brings instability.
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I had some crepe-soled shoes that used to squeal loudly on the polished lino of the school corridors as I oversteered wildly round round the corners (I oversteered in those days).
Fast dogs, greyhounds, lurchers and the like, oversteer owing to the rear bias of their power delivery and their weight distribution. Terriers of all descriptions understeer for analogous reasons, as do hyaenas of course. Cats have neutral quattro handling but poor grip on certain surfaces.
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" all FWD cars are compromised"
Yes.
1. If you drive FWD regularly, you may not notice the understeer, but you end up taking sharp corners (e.g. roundabout exits) more slowly.
2. Try pulling away even slightly quickly with the steering turned in an FWD car and you'll get lots of wheelspin, especially in the wet.
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I had some crepe-soled shoes ...
I have fond memories of brothel-creepers too.
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I think it's a general dig at how you continually mention the wondrous nature of your E39 530i Sport and how nothing else can possibly match it. Yes BMWs drive well but they aren't the be all and end all that you'd like to make them out to be.
Where have I done that in this thread? This is a thread about two different types of drivetrain in general, not about specific cars. I've driven a few more RWD cars than just my own, my experience of RWD is not limited to a single car.
I never mention my own car unless it's a thread about BMW's, its relevant (ie car tax or insurance threads/running cost threads) or somebody else brings it into the discussion.
Much like the case in this example. Somebody specifically ASKED me what I drove.
Edited by MichaelR on 26/08/2008 at 19:25
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I've sat in the passenger seat of an Audi A4 when the driver had it oversteering at 130! It's a FWD car.
I've also had some worrying understeer from the Boxster, that really isn't much fun. Certainly nowhere near as much fun as some throttle induced tail out action can be.
However almost all newer cars hand;e so neutrally with just a little designed in understeer unless deliberately balanced or provoked away from that then in general everyday use on public roads that there really is very little difference unless you're pushing on hard.
Far more greater differences can be made by changing the suspension geometry, however as most people get to drive small FWD cars and large powerful RWD cars then they tend to notice more the effects that these have than the driven wheels make.
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I have driven front wheel drive cars for 12 years now 3 mondeos and present a focus and a astra works van but i still miss the RWD like cortina's and sierra's i used to own.
Pulling away on a hill when roads are damp FWD no matter how carful you are will spin
the wheels RWD never have that problem.Also IMO you can put the power down quicker coming out of corners and how i do miss the fish tailing.I wish main stream car makers would go back to RWD
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Put this argument to bed and buy a Subaru. :-)
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I learnt to drive on RWDs and loved them ever since. I now drive FWD car most of the time. Its a world away from the BMW I owned in so many ways and I don't get to the point where FWD will make a difference to the way my car handles, corners etc. By contrast I regularly used to disconnect the mollycoddling software especially on damp roads in North Wales, to get that rear end out now and again. Somewhere on this site is chronicled a 3.00am pleasure drive from Capel Curig to Llanberis in foggy mid-July weather - that was one of the drives of my life and I wouldn't have had that pleasure in any other car. I couldn't believe that night actually being caught up by another car (the Beemer was flat out) I let it past in the end and saw it was a Scoobie. As I say a very memorable drive that was real RWD pleasure - nothing else could come close. My opinion though - nothing else.
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A RWD, rear engined performance vehicle would be the most challenging to the inept or the self appointed heroes of the road. These front engined cars are all so mundane.......
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Handling aside, RWD cars are more refined.
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My Westfield was very advanced technologically. You could steer it by the conventional method using the steering wheel but it also had the facility to be steered from the back using the throttle pedal.
;-)
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I had an E28 ? BWM 535i as a borroed car . It was similar to the Westfield!
As for not spinning the rear wheels, you could spin them in 1st and second on dry roads and 1,2 ,3 and 4th gear in wet roads . Rear tyre life was around 8,000 according to the regular driver.. And without traction control it was entertaining.
It would have been undriveable in snow due to the torque and wide wheels... (wel,l wide for the time!).
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The snow thing is a pain. I have 265 width rear tyres so it I don't even bother to find the keys when its snowing.
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Since when were the only RWD and AWS cars made in Bavaria?
The vast majority of RWD cars on the road are made by Mercedes and BMW. BMW outsells Mercedes in the UK. You drive a BMW.
Just putting 2 and 2 together....
Your dismissal of FWD proves you have never driven a decent handling FWD car in anger. There are front wheel drive cars out there with poise, throttle adjustability and turn in sharpness which a lot of RWD cars simply don't get close to. A Peugeot 205 GTI is as tricky as any RWD car to master on the limit, and just as rewarding if you get it right. It spat as many experienced road testers off road and track backwards as a contemporary M3, yet is nigh on untouchable on the right road with the right driver.
For what it's worth, all other things being equal, I prefer RWD too, but there have been some absolutely corking handling front wheel drive cars over the years.
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I've driven decent FWD cars. They were a lot of fun. You'll note I said that FWD was for 'small town cars'. IMHO, the cars you mention come under that blanket. One of the most fun drives I've had was in a Clio 182 Cup. A small town car, that was FWD.
When the car gets bigger, however, FWD has siginficant shortcomings hence my opinion that RWD is superior and FWD is for learner cars, small town cars, and stuff built to a price.
I had a Mondeo for a few years. It was a great car, but this was despite being FWD rather than because it was FWD.
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>>stuff built to a price
A truly meaningless phrase - Just about everything (with the exception of things specially built for oil sheiks!) is built to a price - your BMW included.
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I've had 4 RWD cars, the last being a 2.6 Omega. That "seemed" to go round corners okay - flatter than the first 2.0 litre one I had - I think they stiffened up the springs on the later cars.
I must be a wuss as I never got anywhere near its limits. Its a big car - BMW 5 series sort of size. How on earth do you get a vehicle that size to misbehave on our roads today?
Would love a professional driver to show me how its done in my own car to seewhat its capable of and how to exploit it - you know, scruff of the neck stuff.
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Cant say I have ever driven a car that I didnt know whether it was front, rear or all wheel drive before I even opened the door.
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