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Discussion Starter · #1 ·
I watched the Fully Charged look at the EV6 earlier. I was disappointed to hear that the 2WD version will be rear wheel drive. Am I just being old fashioned in not liking the idea of a rear wheel drive car? My most recent experience of that was a friend who gave up on a RWD BMW one winter into owning it as he couldn't control it in even moderately slippery conditions. Is there anything about an EV that would make driving a RWD version any safer/more pleasant than an ICE equivalent?

I haven't watched anything on the Hyundai 5 yet - is that the same?
 

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Is there anything about an EV that would make driving a RWD version any safer/more pleasant than an ICE equivalent?
All comes down to the traction control and stability control system.

The Tesla version works quite well, but not so much the Renault one. Wouldn’t want a RWD Zoe with this system.

So you’ll have to test drive one, but I suspect you won’t be able to truely test it unless you’re on a track to air field.
 

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I drove a rear wheel drive Tesla for a couple of months and it was absolutely fine as far as I could tell it felt no different to drive than any other car so I would agree with the comment above that if the manufacturer gets the system right it feels fine. The Tesla had a lot of power going through the rear wheels but I never managed to get it to misbehave and it felt better in bad conditions than the rear wheel drive Mercedes I owned for years.
 

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A big part of why FWD ICE cars are good in snow is because you have a heavy engine over those front wheels. And conversely, RWD ICE cars tend to have the engine in the front and not over those driven wheels. Back in the days of most mainstream cars being RWD, people would leave extra weight in the boot if snow/ice was expected, to help out.

That's not so applicable to EVs where most of the weight is in the battery, and it tends to be spread around the chassis.

In all cases, suitable tyres are a much bigger factor. Things like BMWs don't have any issues in snow in places that fit winter tyres as a matter of course.
 

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RWD in theory handles better, but i guess it depends what exactly you mean by handling. Snow traction isnt generally what a motor journalist would deem "handling"

Many EV's seem to be going this route. the ID3/4 and associated models are also all RWD too. I presume its for packaging. You can neatly fit the drive motor under the rear boot floor and thus shrink the "engine bay" at the front, increasing cabin room for a given vehicle size.

Oddly enough, the transition from RWD to FWD in the ICE world was also for packaging cabin space reasons. RWD ICE had longitudinal engines and huge gearbox tunnels all encroaching into the cabin area. By turning the engine and switching to a transaxle, you could move the engine/transmission forward and shorten the engine bay, opening up the cabin.
 

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A big part of why FWD ICE cars are good in snow is because you have a heavy engine over those front wheels. And conversely, RWD ICE cars tend to have the engine in the front and not over those driven wheels. Back in the days of most mainstream cars being RWD, people would leave extra weight in the boot if snow/ice was expected, to help out.

That's not so applicable to EVs where most of the weight is in the battery, and it tends to be spread around the chassis.

In all cases, suitable tyres are a much bigger factor. Things like BMWs don't have any issues in snow in places that fit winter tyres as a matter of course.
I think additionally, FWD behaves in a more predictable (and instinctive) way when limits are exceeded.
If you overcook things in a front drive car and lose traction, you usually get understeer, and the natural reaction to lift off the power and/or break increases traction on the front wheels due to weight transfer, stopping the understeer.
If you overcook things in a rear drive car, you might get understeer or oversteer depending exactly what you've done, and if you end up with oversteer, lifting off and/or braking will usually make it worse, as your transferring weight away from the wheels that are already sliding.

Thus when FWD cars started to proliferate in the 80's, when many drivers will have experienced oversteer in their previous rear drive cars, suddenly this new front drive was significantly more predictable and this was seen as a huge advantage.

However modern traction and stability control really changes all of that. You could be really fairly silly in my old E90 330d, and the traction control would dance such a fine line that you didnt even know it was doing anything, unless you happened to glance at the dashboard and catch the flashing light. And even if you really tried to provoke it, ie going full throttle at low speed while taking a sharp corner, the ESP system would immediately catch and fix it, in a really quite impressive way.

But yes, your tyres point is the crux here. A RWD car on winter tyres will be better than a FWD one on summer tyres.
 

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Discussion Starter · #8 · (Edited)
Thanks to all for your input. Unfortunately I can remember back to when FWD cars were becoming the norm, and although I didn't drive then I can remember the surge of enthusiasm for how much "easier to drive" they were than RWD.

It's good to hear that a decent set of tyres, traction control and the weight of the motor over the wheels are all in favour. Back to dreaming now of the Hyundai 5 or Kia 6 as my next car lol. :)
 

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I’d choose RWD over FWD in most situations. The front wheels do the steering uncorrupted by the power. It takes a bit of adjustment in driving style but should generally feel nicer to drive. I don’t think VW would have put all their electric eggs in that basket if they were worried about safety (not sure if that’s a good example, but you know what i mean).
 

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BMW are notorious for fitting wide, low profile and sport orientated tyres on even their most inappropriate M-Sport badged cars. Which is unhelpful in snow. Easily fixed with winter wheel set.

All comes down to the traction control and stability control system.

The Tesla version works quite well, but not so much the Renault one. Wouldn’t want a RWD Zoe with this system.

So you’ll have to test drive one, but I suspect you won’t be able to truely test it unless you’re on a track to air field.
Interesting as Renault are one of the few manufacturers to sell a RWD hatch back.
 

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I too would always choose a RWD car over a FWD.

If you overcook things in a front drive car and lose traction, you usually get understeer, and the natural reaction to lift off the power and/or break increases traction on the front wheels due to weight transfer, stopping the understeer.
If you overcook things in a rear drive car, you might get understeer or oversteer depending exactly what you've done, and if you end up with oversteer, lifting off and/or braking will usually make it worse, as your transferring weight away from the wheels that are already sliding
Hmmmm...

So, I agree if you "overcook" it in a FWD car, you get understeer - true - but it's the reason FOR that understeer that is the problem. If it's simply carrying too much speed into a bend, then lifting off will cause the weight to shift forward, and then you get "Snap oversteer" - which unless you are very quick will spin you round like a top - most modern stability systems do mitigate this a degree. However if it's plough on understeer caused by too much power applied, then the sliding wheels are also the wheels you are trying to steer with. A reduction in power then can cause the wheels to stop spinning - quite often the driver has wound too much lock on... and hey presto it's spin time again. Again the modern traction controls will deal with this well.

In a RWD car, the steering isn't corrupted by having to transmit the power as well. Most modern Stability systems will cut power / apply single wheel braking to stabilise this long before the driver has a major issue. Also, usually oversteer will be caused by too much power which again you can dial back - but as the rear wheels have already lost traction, usually lifting off will cause a slide, but a much less "snappy" one - and more easily controlled.

With modern cars it doesn't really matter a jot, Stability controls will deal with most events pretty well. Less weight on the front (ICE cars) means steering needs less power assistance on RWD than FWD so the steering is often more "feelsome" and thus much nicer to drive - but I am not sure how true that is on EV's - but you won't get torque steer on a RWD car unlike a FWD.

And for winter - yes I think a RWD EV will probably be much the same as a FWD except again you aren't corrupting the front tyres by trying to get them to cope with all the power AND all the steering - but you can't beat all seasons tyres come November, that is undeniable - I've towed Discovery's on road tyres out of snow or fields with my old ML500 - because I had All Terrain Tyres on 12 months of the year.

But which would I buy? RWD every single time given a choice.
 

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Thanks to all for your input. Unfortunately I can remember back to when FWD cars were becoming the norm, and although I didn't drive then I can remember the surge of enthusiasm for how much "easier to drive" they were than RWD.

It's good to hear that a decent set of tyres, traction control and the weight of the motor over the wheels are all in favour. Back to dreaming now of the Hyundai 5 or Kia 6 as my next car lol. :)
I nearly bought an ID3 simply because of its rear wheel drive. All wheel drive is my ideal setup, having had 3 fixed all wheel drive vehicles - Rav4, Subaru Outback and Alfa Brera 3.2Q4 and all had fantastic handling as well as being unstoppable in the winter.
FWD was, as per usual for the motor industry a means to save money and leave more space for the occupants. It was most definitely not done for reasons of handling or safety.
 

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Many EV's seem to be going this route. the ID3/4 and associated models are also all RWD too. I presume its for packaging. You can neatly fit the drive motor under the rear boot floor and thus shrink the "engine bay" at the front, increasing cabin room for a given vehicle size.
I wonder how much of this switch to rear wheel drive is also to allow the wheelbase to be increased and still retain the needed level of crashworthiness? It seems to me that there are big advantages in having empty space up front as it allows for bigger crumple zones without that space being taken away from useful volume inside the car which has to be a good thing.

It will be interesting to see how car shapes evolve now that they have lost the contents of one of the traditional three boxes needed, the engine space the passenger space and the boot space. With a drive unit that is not much bigger than a conventional rear axle that must really free things up for the designers. I get the feeling that they are being really conservative at the moment and keeping electric car designs too similar to ICE cars when they could make some really big changes if the buying public would accept them.
 

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hmmmm...

So, I agree if you "overcook" it in a FWD car, you get understeer - true - but it's the reason FOR that understeer that is the problem. If it's simply carrying too much speed into a bend, then lifting off will cause the weight to shift forward, and then you get "Snap oversteer" - which unless you are very quick will spin you round like a top - most modern stability systems do mitigate this a degree. However if it's plough on understeer caused by too much power applied, then the sliding wheels are also the wheels you are trying to steer with. A reduction in power then can cause the wheels to stop spinning - quite often the driver has wound too much lock on... and hey presto it's spin time again. Again the modern traction controls will deal with this well.

In a RWD car, the steering isn't corrupted by having to transmit the power as well. Most modern Stability systems will cut power / apply single wheel braking to stabilise this long before the driver has a major issue. Also, usually oversteer will be caused by too much power which again you can dial back - but as the rear wheels have already lost traction, usually lifting off will cause a slide, but a much less "snappy" one - and more easily controlled.

With modern cars it doesn't really matter a jot, Stability controls will deal with most events pretty well. Less weight on the front (ICE cars) means steering needs less power assistance on RWD than FWD so the steering is often more "feelsome" and thus much nicer to drive - but I am not sure how true that is on EV's - but you won't get torque steer on a RWD car unlike a FWD.

And for winter - yes I think a RWD EV will probably be much the same as a FWD except again you aren't corrupting the front tyres by trying to get them to cope with all the power AND all the steering - but you can't beat all seasons tyres come November, that is undeniable - I've towed Discovery's on road tyres out of snow or fields with my old ML500 - because I had All Terrain Tyres on 12 months of the year.

But which would I buy? RWD every single time given a choice.
I do agree with your general premise, but the simple fact is that the way typical drivers seem to get into trouble, tends to be in a manner which FWD cars are generally just better at dealing with. I guess Mrs Mavis in her Vauxhall Astra isnt generally carrying too much speed into a corner and snap oversteering into a hedge. Its probably more applying power out of a wet/slippy corner or junction with a little too much zeal. Certainly with my personal experience, power-on understeer is certainly most common that i've experienced in the plethora of front drive cars over the years, and its generally super controllable and easily fixed. I'd happily ride that limit of understeer on a wet roundabout for instance.

Modern chassis tuning also makes snap oversteer much less likely.

Power on oversteer in a rear drive car though, i'm super wary of. Its much less predictable, less easily fixed, and much more likely to go badly wrong.

For instance I ran a 330d for some years before the EVs, and i recall one such "oh shit" moment, on the exit of a roundabout heading onto a motorway slip ramp. It was one of those dualed sliproads, nice and wide open, and as i steered towards the exit i floored it, expecting a nice blast down the sliproad... and with zero warning the rear snapped sideways. I dont know wether it was diesel or something on the road or if i just upset the car over the camber change. The stability control caught it and fixed it before my brain even had time to react. But had that been a 1987 Sierra 2.0 GLX, i'd have been upside down in the barriers :ROFLMAO:

For actual handling, RWD clearly wins out, as per you describe theres less interaction between power and steering and it makes everything just that bit "nicer".
 

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I agree to an extent - I think part of the public's reluctance is that they already look "different" - The Kia's are very polarising over their looks (not the prettiest I grant you) and some others just look awful.

I like the ID's (outside not inside) but I think we'll see some "traditional" designs to appeal to older buyers and "revolutionary" for the ones who want something different.
 

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One difference between EVs and ICE vehicles is the instant torque and from zero mph. This could make a rear wheel drive EV trickier on non dry roads and require a well sorted ESP to save some clumsy drivers.

On a postive note, the weight distribution is usually a lot better than with ICE vehicles.
 

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i steered towards the exit i floored it,
in a 330d.... that might be your problem right there lol. I have to say a 330d is a blimmin quick car, also has a bit of turbo lag and then a thump of torque - so if you aren't in a straight line, flooring it isn't an option! Whereas my old 1970's Ford Escort Mk 1 1.3... .well flooring it then didn't result in much happening at all!!

I too have had those moments - one of mine in a Ford Capri, a roundabout and the damp.... ooooh that was interesting....

However modern traction controls make all that pretty much irrelevant - Ferrari for example have tuned it so even an amateur could hold a dramatic drift!!

The reality is, a well sorted EV can meter it's power very progressively - combine that with modern stability controls, and I think the simple answer is, FWD or RWD will be safe - RWD should be able to be "nicer" to drive.
 

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One difference between EVs and ICE vehicles is the instant torque and from zero mph. This could make a rear wheel drive EV trickier on non dry roads and require a well sorted ESP to save some clumsy drivers.

On a postive note, the weight distribution is usually a lot better than with ICE vehicles.
Yes, but also very progressive and well controlled. I can spin the wheels on mine easily - but I'd have to want to - I can pull away delightfully smoothly if I want to....
 

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Yes, but also very progressive and well controlled. I can spin the wheels on mine easily - but I'd have to want to - I can pull away delightfully smoothly if I want to....
i agree, but some drivers are clumsy, not mentioning any particular gender. ;)
 

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RWD much preferred over Front WD. The reason the i3 is a good drive is due to this. The Kona, Niro are pretty horrible with torque steer. Glad Kia have gone down this route.
 
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