Do folk really perceive RWD to be dangerous?

[Kawasicki]

Hasbeen said:

Sorry Garvin you have got some of that quite wrong.

Loosing the tail under acceleration is a factor of wheel spin, or at least slip, starting towards spin.

Back off oversteer is a phenomena of front drive, & I have never experienced it in a rear wheel drive car. Lifting off when the back starts to slide will bring the tail back instantly. Just don't muck with the steering at the same time.

I have driven a few, including F1 & F2 Barhams & Lotus open wheelers along with Holden dealer team Monaros at Bathurst. I was a specialist in wet conditions, when controlling wheel spin was everything.

I will agree with you completely that too much opposite lock has sent many cars backwards into the scenery, when what was required was just a little reduction in pro turn lock. This is particularly the case in things like the S2000, with it's too light too direct steering. Mine has tried to bite me a couple of times, & it is obvious how the inexperienced get into trouble with them. Just a couple of inches of steering wheel movement has a lot of movement of the road wheels.

One of the problems today is wide tyres. I used to be able to drive stock Holdens & Fords to the snow on normal tyres no problem, when they ran on 4" wide steel wheels. The Bathurst Monaro was a little more difficult on 6" wheels & tyres, but only a little. Todays wide tyres have trouble biting through water or snow.

With our young lady, just backing off may have had a following car in her boot, but would never have caused her to spin, unless on ice.

To cancel power oversteer, you reduce the power, agree with you there.

I have to disagree though that rwd cars don't oversteer when backing off the throttle, most road cars do. If you are cornering at the limit and you lift off, most cars move into oversteer. Some quickly, some slowly, some instantly, some delayed, but most road cars (fwd or rwd) do it. In fact it is usually a bad sign if a car does not eventually oversteer, as that is normally a sign of a non adjustable set up.

[stargazer30]

Try RWD with an engine over the rear, no ESP, and fettled with an aftermarket turbo, plus no weight. Then add inexperienced RWD driver used to FWD hot hatchs with all manor of safety aids, and rain.

I mean what could possibly go wrong?!

I really miss that car, but it is the only car I've ever been scared to drive.

[Hol]

Steve_F said:

Hol said:

Some people have the misconception that AWD cars will stop better in the snow, but in reality the have the same tyres as everyone else - and the same problems with sliding on ice. Been there, so I know.

Assuming the BMW guy in the picture can get enough traction to get going, he will also actually be better off when goes down a compacted snow/icy hill where the comparible BMW guy next to him with chains on the back will have no steering capability (apart from bouncing off the kerbs).

Try telling that to the Forester I had, the engine braking was much more noticeable than anything FWD or RWD that I've driven. Used to drive up to traffic lights at the same speed as the car in front every night and slow down by downshifting as they were on the brakes until the last phase where the clutch had to be used.

Not sure in the Cherokee as it's an auto but with increased engine braking an AWD should be better at slowing down in snow and ice as the driver can use less force through the brakes.

Can definitely see the logic in the chains on the front though, get it moving and keep going and they should be ok...

I have owned two Forester Turbos and I admit to going out in the snow for fun as their assymetrical AWD was perfect for forward momentum going UP a snowy/icey hill. I also have a pair totally unused Forester sized snowchains in my garage loft, as I never needed them over 7 winters.

But despite its grip in getting me up hills and through deep snow, it had the same problem with physics that every other car on summer spec tyres has - when going DOWN an Icy slope (the hilly type, not a cold TG china-man).

My point is that the tyres would loose physical adhesion, due to the weight of the car overwhelming the ability of the front tyres to grip to the slippery surface.

[mikey k]

deltashad said:

The younger generation have been brought up with FWD so are probably a bit fearful of the unknown.

Its not the younger generation, its the vast majority.
They aren't fearful just blissfully unaware until it rotates on them

For example

[Monkeylegend]

mikey k said:

deltashad said:

The younger generation have been brought up with FWD so are probably a bit fearful of the unknown.

Its not the younger generation, its the vast majority.
They aren't fearful just blissfully unaware until it rotates on them

For example

Helps front end grip when braking.

[mikey k]

Especially as the rear overtakes the front

[J4CKO]

Lost soul said:

J4CKO said:

Back when RWD was the norm, most cars your average punter could buy were 60, 70, maybe 100 bhp, the odd exceptions were 130 - 140 bhp V6 Capris, nowadays even cooking BMW 1 series have 150 odd, ranging up to 300 ish for the 135i, power is much more accesible and I do think that without ESP there would be a lot more accidents, especially with the torquey turbodiesel engines.

back then a 3lt Capri or RS1600 Escort were the dog's in the every day performance car world with 100-140 bhp or so and an Etype was a rare beast

I used to drive my father in laws V12 Etype, I knew not to provoke it in the wet but it wasnt too bad, think the rear IRS helped, relative to the Fords, still, it felt long, had very light steering and was a bit ponderous, woudl love to try a six cylinder one as I think that is what the E-Type was really about.

[samvia]

Kawasicki said:

To cancel power oversteer, you reduce the power, agree with you there.

I have to disagree though that rwd cars don't oversteer when backing off the throttle, most road cars do. If you are cornering at the limit and you lift off, most cars move into oversteer. Some quickly, some slowly, some instantly, some delayed, but most road cars (fwd or rwd) do it. In fact it is usually a bad sign if a car does not eventually oversteer, as that is normally a sign of a non adjustable set up.

This I can vouch for, I ended up backwards in the grass halfway throgh Coram at Snetterton a couple of months ago, due to a big mid-corner lift in the M3 as I caught a line of cars in front mid-corner.

[MC Bodge]

Hasbeen said:

Sorry Garvin you have got some of that quite wrong.

Loosing the tail under acceleration is a factor of wheel spin, or at least slip, starting towards spin.

Back off oversteer is a phenomena of front drive, & I have never experienced it in a rear wheel drive car. Lifting off when the back starts to slide will bring the tail back instantly. Just don't muck with the steering at the same time.

I have driven a few, including F1 & F2 Barhams & Lotus open wheelers along with Holden dealer team Monaros at Bathurst. I was a specialist in wet conditions, when controlling wheel spin was everything.

I will agree with you completely that too much opposite lock has sent many cars backwards into the scenery, when what was required was just a little reduction in pro turn lock. This is particularly the case in things like the S2000, with it's too light too direct steering. Mine has tried to bite me a couple of times, & it is obvious how the inexperienced get into trouble with them. Just a couple of inches of steering wheel movement has a lot of movement of the road wheels.

One of the problems today is wide tyres. I used to be able to drive stock Holdens & Fords to the snow on normal tyres no problem, when they ran on 4" wide steel wheels. The Bathurst Monaro was a little more difficult on 6" wheels & tyres, but only a little. Todays wide tyres have trouble biting through water or snow.

With our young lady, just backing off may have had a following car in her boot, but would never have caused her to spin, unless on ice.

Great post, from a viewpoint of more experience, and probably skill, than 99.9% of the people here.

Road cars driven by joe public do lift off oversteer though. Somebody who knows what they are doing and does it well might not encounter it, though.

I don't know what the S2000 driver actually did, I just heard about it from her husband, who wasn't very happy, as it was his idea to trade her 1.0 206 for the S2000

I was just responding to the person who seemed to think that RWD S2000s would be fine for everybody.

People mostly drive cars that are easy, benign and forgiving nowadays. The skills required for twitchy RWD that were normal in the old days have been forgotten.

[DavidJG]

samvia said:

This I can vouch for, I ended up backwards in the grass halfway throgh Coram at Snetterton a couple of months ago, due to a big mid-corner lift in the M3 as I caught a line of cars in front mid-corner.

Some RWD cars that demonstrate lift-off oversteer in extreme: Triumph Vitesse Mk1 / GT6 Mk1. Never, ever, lift off mid corner! The resulting lift-off oversteer is quite spectacular. The Mk2 versions are much better controlled thanks to a re-designed rear axle. Almost any pre-89 911 will also give some very impressive lift-off oversteer (been there a few times and always managed not to hit anything, more by luck than judgement though).

[RobM77]

Kawasicki said:

Hasbeen said:

Sorry Garvin you have got some of that quite wrong.

Loosing the tail under acceleration is a factor of wheel spin, or at least slip, starting towards spin.

Back off oversteer is a phenomena of front drive, & I have never experienced it in a rear wheel drive car. Lifting off when the back starts to slide will bring the tail back instantly. Just don't muck with the steering at the same time.

I have driven a few, including F1 & F2 Barhams & Lotus open wheelers along with Holden dealer team Monaros at Bathurst. I was a specialist in wet conditions, when controlling wheel spin was everything.

I will agree with you completely that too much opposite lock has sent many cars backwards into the scenery, when what was required was just a little reduction in pro turn lock. This is particularly the case in things like the S2000, with it's too light too direct steering. Mine has tried to bite me a couple of times, & it is obvious how the inexperienced get into trouble with them. Just a couple of inches of steering wheel movement has a lot of movement of the road wheels.

One of the problems today is wide tyres. I used to be able to drive stock Holdens & Fords to the snow on normal tyres no problem, when they ran on 4" wide steel wheels. The Bathurst Monaro was a little more difficult on 6" wheels & tyres, but only a little. Todays wide tyres have trouble biting through water or snow.

With our young lady, just backing off may have had a following car in her boot, but would never have caused her to spin, unless on ice.

To cancel power oversteer, you reduce the power, agree with you there.

I have to disagree though that rwd cars don't oversteer when backing off the throttle, most road cars do. If you are cornering at the limit and you lift off, most cars move into oversteer. Some quickly, some slowly, some instantly, some delayed, but most road cars (fwd or rwd) do it. In fact it is usually a bad sign if a car does not eventually oversteer, as that is normally a sign of a non adjustable set up.

Samvia said:

This I can vouch for, I ended up backwards in the grass halfway throgh Coram at Snetterton a couple of months ago, due to a big mid-corner lift in the M3 as I caught a line of cars in front mid-corner.

I just thought I'd have a go at clearing the confusion up. What's being discussed here are two things:

1) Power oversteer, which I think we're all clear about: too much power loses grip so that end starts to slide more.

2) Weight transfer (bear with me, we'll get to LOO), which is a term referring to what happens when you gain or lose speed in a car, by whatever means. When a car gains speed, the front will go light and the car will increase its tendency to understeer, and when a car loses speed the reverse will happen - the back end will go light and increase the car's tendency to oversteer. Obviously you need to couple this with the chance of power oversteer if the increase in speed is by pushing the throttle pedal, and factors 1 & 2 here will contribute different amounts depending on the car's speed, the grip available, the shape of the slip/grip curve (i.e. ratio of static to dynamic friction - whether it's wet or not), the car's power, grip levels etc. However, back to weight transfer: in every car I've ever driven (front, 4 and rear drive road and racing cars), slowing down brings about a tightening or a lessening of line, rather than what we would refer to as full blown oversteer (i.e. opposite lock required). To demonstrate this point to someone a few years ago, I piled into a curving motorway slip road in my Elise at speed, on the limit, and then backed off to show the lack of drama, and then actually braked heavily - the nose tucked in sharply requiring me to back off the steering to prevent oversteer, but the car did not oversteer in the colloqiual sense that we mean (opposite lock) - in fact you could even do that in the single seaters I used to race, or the FWD saloon, RWD sports cars etc. Some racing corners actually require braking through them, for example at Snetterton the Esses or the exit of Coram into Russell. You normally look to lessen the curvature with your racing line so you can devote more grip to braking rather than cornering, but it's perfectly possible to brake whilst cornering.

"Lift off oversteer" is indeed a real phenomenom, as we all know, but it happens when you combine the above weight transfer effects with too much steering lock, and usually slow reactions: the nose of the car will get more grip when you back off, and the inappropriate amount of lock will cause the car to steer sharply into the corner, which when combined with a light rear end and enhanced front grip and steering response, and a driver who isn't in tune with steering and reacts half a second after the car does anything, this will cause "lift off oversteer". This is primarily a driver steering error - backing off or even braking should be harmless in a corner if you can steer well and in sympathy with the car rather than reacting to what it's just done. When a car starts to understeer, which most do at speed ina corner, the natural tendency is to put in a bit more lock, but with this you get diminishing returns (this is as the slip/grip curve tails off) and a skilled driver will find a sweet spot and not give the car any more lock after that. Such a driver (perhaps Hasbeen's experiences quoted above with RWD racing cars are relevant here), will never experience lift off oversteer. I've been a passenger in cars that have oversteered and even spun under lift off, and in every example the driver simply had too much lock on beforehand and then lifted off the power.

The reason that LOO is associated with front drive cars is probably that they tend to understeer more at the limit, so it's more likely that a driver will put in an inappropriate amount of lock when cornering.

One of the most important skills to learn when driving is steering, and in this case that means not thinking of the steering as simply steering the car, but adjusting the steering so that the car points to where you want to go (which are two different things if you think about it). For example, if you need to slow in a corner, then you can, but you just need to be sympathetic to what the car needs in terms of steering lock to hold its line. In an ideal bend the car will be at a steady speed and the steering will be still, but if you back off then you must decrease the amount of steering accordingly - not reactively to the car, but pro-actively, sympathetically and with a light touch to feel what the car needs. This is analagous to reaching forwards for something when stood up - you need to stick a leg out behind you to counter-balance yourself - most of us do this instinctively as we reach; if we reacted to our instability we'd probably fall over or wobble around like a clown. A good driver should steer instinctively so the car stays on the line they want, a bad driver will react to what the car's just done, which when combined with lifting off and having too much lock on, causes lift off oversteer.

So LOO will happen in FWD or RWD, but as explained above I think it's more likely that drivers will find this in a FWD car as their inherent nose heavy nature means they tend to understeer more than RWD cars and that leads to too much lock for a lot of drivers. LOO is also very likely in a true rear engined car, as the light front end means more understeer (for different reasons this time), plus in that case it's even more evil because the high polar moment of inertia and rearward weight balance cause things to get nasty quite quickly as the rear tries to overtake the front. Another factor can be softness of suspension and the height of the car's CofG - many mid or rear engined road cars will put their weight just where you don't want it during LOO and things can get nasty quite quickly (e.g. Testarossa, 348, early mk2 MR2s). The Elise is a classic example of this, in that whilst the car is beautifully responsive and has thoroughly well engineered handling, there's no getting away from the fact that about 70% of the weight's over the rear in quite a tall transverse engine. My 3 series actually handles 'better' in that sense than my Elise did or my 2-Eleven does, but obviously there's more to handling than inherent balance, which is why I prefer the handling on the Lotuses. Keep things tidy, gentle and smooth and you shouldn't really run into problems.

I hope that makes sense and I didn't ramble too much!

As for the OP's original question, I think it's just down to mis-conceptions, probably partly fed by all marketing nonsense manufacturers put out to support FWD when it was introduced en masse years ago to increase cabin space and cut production engineering costs for cars. In addition to this, most drivers only reach the limit in the snow or perhaps greasy wet conditions, when the gentle and intuitive weight transfer effects I mentioned above are massively over-shadowed by power oversteer, which can be quite scary for your average driver, certainly more-so than power understeer. If you took most drivers up to high speeds on a dry or even a moderately wet track in FWD and RWD cars then I'm pretty confident than most would end up preferring RWD - that's certainly my experience anyway. As it is Joe/Jane Public drives too slow to notice the difference, unless it snows, in which case they feel safer in FWD, for very understandable reasons. Couple that with the lower production costs and greater interior space and it's pretty obvious why most mundane shopping or commuting cars are FWD. I just hope that the likes of BMW and Mercedes continue to make practical everyday cars that also have RWD and handle well - I'm really not a fan of FWD, at least not for a daily driver road car.

[jamieduff1981]

I've got no racing background but in road driving my Cerbera needs a reduction in power to check a wandering rear end if excess power was the cause in the first place.

I'll admit I've never plowed in to a corner that fast that I've actually had the back end slide a long way out, but I reckon that would result in a spin either way. I tend to enter corners and try to maintain just enough throttle to avoid any major acceleration or engine braking, and the sensation I get when venturing away from this is that the back end starts to creep so I think a sudden lift mid-bend would also cause a very wayward back end.

When the cornering under power and the rears spin up and the back end steps out, a quick reaction to reduce power does the trick. Trying to 'ride it out' would, I am certain, result in some wild fishtailing before a majestic yaw and disappearance off in to the scenery like so many Youtube clips of inexperienced people who have bought a Corvette or Mustang and tried to show off for a camera.

[otolith]

RobM77 said:

When a car starts to understeer, which most do at speed ina corner, the natural tendency is to put in a bit more lock, but with this you get diminishing returns

So they put a bit more in. And that doesn't work either, but they keep trying. Then they give up and lift or brake.

I remember reading something Jackie Stewart wrote about this when I was a young driver, and not having enough pieces of the puzzle to get my head around what he was describing. I'm sure it's how a lot of hot hatches get crashed. By the time I got an S2 Elise, I understood this, and at first I couldn't understand how they were catching people out because I didn't habitually drive in that way. Having since provoked it on purpose, I can see exactly how people crash them in that manner.

[motco]

Baryonyx said:

NiceCupOfTea said:

What I've never understood:

E36 compact and z3 roadster - crap handling and rear suspension
E30 - excellent fun tail out handling

Same rear end isn't it?

That is a good point. I've always thought the snide remarks directed at the Z3's rear suspension were a bit iffy considering the E30 is a reasonable handler and the Z3 was never meant to handle with the finesse of a Boxster or whatever (it was conceived as a GT for the US market IIRC).

Did the Z3 also have a slightly wider rear track and tyres?

I have a late model 2.2 Z3 Sport and also a Westfield. I took the Z3 on a trackday one December because it was quite honestly too damned cold for the Westfield and I'd got the booking which would go to waste otherwise. It doesn't handle well as the Westfield, obviously, but it's a bloody sight better than the 'critics' would have you believe. Unlike most FWD cars, it didn't plough on with understeer nor did it lose its back end dangerously either as the RWD naysayers tell you. Judicious use of the throttle could keep it neither under nor oversteering around an airfield circuit in the dry. The only failing I could identify apart from lack of real grunt, was the brakes' tendency to dive for cover after a couple of laps due to overheating.

[RobM77]

otolith said:

RobM77 said:

When a car starts to understeer, which most do at speed ina corner, the natural tendency is to put in a bit more lock, but with this you get diminishing returns

So they put a bit more in. And that doesn't work either, but they keep trying. Then they give up and lift or brake.

I remember reading something Jackie Stewart wrote about this when I was a young driver, and not having enough pieces of the puzzle to get my head around what he was describing. I'm sure it's how a lot of hot hatches get crashed. By the time I got an S2 Elise, I understood this, and at first I couldn't understand how they were catching people out because I didn't habitually drive in that way. Having since provoked it on purpose, I can see exactly how people crash them in that manner.

It's just a basic mis-understanding of how to drive a car. The other factor of course is steering technique - often the LOO driver has no idea where the front wheels are pointing or where straight ahead is.

The weird thing about cars is that 99.99% of people drive them just to get around, and many people who take an interest in track days or who drive faster just use those same skills but just go quicker, whereas for most of other activities involving controlling something (sailing, skiing etc) almost everyone learns a complete skill set, or rudementary skills sympathetic to moving on to learn higher performance skills, from the start because they have an interest in doing it well and perhaps competitively in the future. Conversely, the skills learnt in road driving from the basic and advanced driving tests in no way prepare you for driving a car fast, and they're not meant to because most people just want to drive to the shops. The problem comes when you push the limits and go outside the scope of what you've learnt to do at lower speed, either by accident or intention. Jackie Stewart, who you mentioned, has indeed always been a great advocate for encouraging more thorough skills in drivers that translate to higher speeds, and rightly so in my compartively very humble opinion. I think there are a few principles from the competitive world that all drivers should learn, somewhat because it'll help them in the snow or in extreme situations, but mainly because it's kinder to the car, the passengers and for the percentage of people who do decide to drive faster than the law intends people to, it'll make them safer and less likely to hurt themselves or others. The danger with this approach though has always been that drivers trained in driving fast tend to negate the safety benefits by driving comensurately faster, and there's evidence to prove it. I think something can still be done though if done carefully.

[MC Bodge]

What RobM77 says is correct.

Winding on more and more lock then lifting off in desperation can bring the back around in a big way. As I once experienced a long time ago ....and learned from.

I also scrubbed the writing of various old high-profile tyre sidewalls by the enthusiastic application of steering lock

Going back to the original question, most people don't drive fast enough or concentrate enough to notice subtleties. They want a benign car that will cope at modest speeds (even if people do want big power, they mostly don't use it, other than low
Rpm grunt for the odd traffic Light Grand Prix and to prevent people getting in front of them on the motorway) in all weathers.

They don't balance throttle, rev match, use minimal inputs or progressively feed in clutch, throttle, steering, brakes etc. etc.

A fwd car is good for most of these people.

[SonicShadow]

I think a skid pan day should be a mandatory part of the driving instruction process - for most people, the first time they learn about how a car behaves and responds in low grip conditions is when it goes wrong for them on the public road. Surely it would be better to demonstrate this to every new driver in a controlled environment? Plus it's quite fun when there's no risk of ending up in a ditch or embedded in a hedge

[161BMW]

unpc said:

Baryonyx said:

NiceCupOfTea said:

What I've never understood:

E36 compact and z3 roadster - crap handling and rear suspension
E30 - excellent fun tail out handling

Same rear end isn't it?

That is a good point. I've always thought the snide remarks directed at the Z3's rear suspension were a bit iffy considering the E30 is a reasonable handler and the Z3 was never meant to handle with the finesse of a Boxster or whatever (it was conceived as a GT for the US market IIRC).

Did the Z3 also have a slightly wider rear track and tyres?

Dunno where this myth came from. I had an E30 325i back in the day and it handled quite badly on the limit and was quite unpredictable. A mate's E30 M3 that I drove many thousands of miles in, was sublime. There was nothing wrong with the geometry of my car but fundamentally cooking E30s were pretty rubbish. I guess the more limited wheel travel of the M3 helped reduce the camber change.

You say the E30 325i handled unpredictably while the E30 M3 was the opposite
Did the E30 325i have LSD or not :-) ?

[GravelBen]

Kawasicki said:

GravelBen said:

Controlling that lift-off oversteer is probably easier with Rwd than Fwd for a capable driver as you can balance the car on the throttle and let it gradually hook up, rather than it snapping back into line (or beyond) with a lurch as the speed scrubs off a Fwd and it regains grip.

This. And you don't need to really balance the throttle on a rwd car to still see an advantage. With total throttle lift the yaw rate is usually slower in the rwd car. The advantage of fwd is super fast and clean (yaw damped) lift-off oversteer correction if you get back on the throttle aggressively. Which about 0.01% of the driving population will do.

On gravel roads I've often found that with Fwd, getting back on the throttle too aggressively can just result in wheelspin and the front washing out all over the place with cambers, momentum etc. I expect higher-powered Fwd cars can be similar on sealed roads. Strange feeling in a way balancing a car all from one end!

Rwd definitely gives more options and more transparency in situations like that.

Point well made by Rob above about the difference between dramatic lift-off oversteer and simply tightening the line being dependent on steering input too.

Edited by GravelBen on Friday 24th October 12:38

[GravelBen]

Hol said:

I have owned two Forester Turbos and I admit to going out in the snow for fun as their assymetrical AWD was perfect for forward momentum going UP a snowy/icey hill. I also have a pair totally unused Forester sized snowchains in my garage loft, as I never needed them over 7 winters.

But despite its grip in getting me up hills and through deep snow, it had the same problem with physics that every other car on summer spec tyres has - when going DOWN an Icy slope (the hilly type, not a cold TG china-man).

My point is that the tyres would loose physical adhesion, due to the weight of the car overwhelming the ability of the front tyres to grip to the slippery surface.

Bit off topic here but hey...

While there is of course only so much traction the tyres are able to provide, a decent 4wd system can make better use of that traction in deceleration as well as acceleration. The torque transfer through the drivetrain works both ways to help avoid single-wheel lockups, as well as applying engine braking across 4 contact patches instead of 2. If you just stomp on the brakes and rely on ABS (as many people do!) you probably won't notice any difference though.

It may well be that your icy slope was just too slippery even for engine braking with those tyres, but the 2wd cars traction limit would have been exceeded by more than the 4wd.

It is an interesting experiment to slowly descend a slippery slope in a 4wd using only engine braking to control the speed (especially if in low range), and then see just how little force can be applied on the brakes before the vehicle starts to slide and you lose steering control. Certainly increases your respect for engine braking!