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Memory a fickle jade at best tells me that part of the problem producing Issigoni Mini was the CV joint finally sourced from Hardy Spicer. Cyd probably knows the full history of this episode.
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As I recall it is more expensive to make fwd rather than rwd car if you compare otherwise identical cars.
However, if you wanted to make a rwd car with comparable inside space to that of a fwd car it would be more expensive.
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Can anyone with knowledge answer my original query? Does it cost more to develop and make a FWD car?
I think development costs are pretty similar, with the millions of dollars spent in R&D, the drivetrain costs are lost in the noise compared to engine, body, trim, safety etc.
FWD (and rear / mid engine, rwd) does without the propshaft, I\'d have thought that makes front engine-rwd more expensive.
There\'s not really a like for like case though, Triumph Toledo excepted!
Gareth
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I don't know whether it is more expensive, starting with a clean sheet of paper to make a FWD OR RWD car but I would imagine there is not a lot in it. The FWD allows better passenger space (No Propshaft intrusion)and possibly lower noise levels (less vibration with shorter driveshafts), better traction etc and I suppose there may even be an argument that it gives better braking as the front tyres have greater adhesive weight. To say it is more dangerous is ridiculous, to echo the comments above anyone who had a train set knows how much more stable a train is when being pulled rather than pushed.
I do remember reading comments back in 1982 when the Sierra was launched and it was considered very old fashioned because it was still RWD. At the time it was said that Ford were short of money because of poor American results and could not afford to develop a FWD car
SR
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To say FWD is dangerous is uninformed rubbish. The main problem with FWD has more to do with the conflicting physics of the set up. Trying to steer the driven wheels is difficult and the result is torque steer. FWD cars suffer from power understeer - the car is trying to push in a straight line while the tyres are grimly attempting to go left or right. The reason BMW persist with RWD is to balance the weight of the car as close to 50:50 as possible. I do prefer RWD but this is driving preference because I quite enjoy hanging the rear out! MY current car however is FWD. So ther you go.
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Well said v8....I can't resist disengaging as many driver aids as possible and occasinally letting it all hang out.
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Pugugly
You really should be trying to set an example and not admiting to driving like a lunatic like the rest of us.
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Let's be honest - anyone who grew up in the '60s and experienced the handling characteristics of Austin A40s, A50s, Morris Oxfords, Riley 4/68s, Sunbeam Talbots, Renault Dauphine Gordinis etc, where going through a hedge backwards was an everyday occurrence (roads in N Yorkshire didn't have any cars on them then!) was astonished by the safe handling of Minis, Triumph 1300s, Morris 1100s and other front wheel drive cars. Yes there was not the excitement of the tail hanging out, and that elusive "4 wheel drift" was unattainable but for the vast majority there was the compensation that you didn't have to explain to your dad why his car was in a field somewhere with a very damaged rear end. And the same applies today. RWD is great for those who can handle it but I suspect that that is considerably fewer than those who THINK they can handle it. Just look at those BMs and MBs that have trouble in the snow/ice
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PhilW. That's pretty much what I was trying to say, in a roundabout way. Some of those old cars were mares really, but we knew no better. I did several 360's in the old days.I remember an incident when my insurance company were very interested to know how I had managed to dent every wing, since nobody else was involved.
Thankfully, the roads were less crowded then so I am glad that the more 'forgiving' FWD cars are popular now. I have to admit that they do 'drive themselves' a bit and take some of the challenge out of motoring.
Growler mentioned the Beetle with its rear engine and drive.I used to enjoy watching them pirouetting around in winter but I never used to come up too close at a roundabout.
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I think there are some incorrect generalisations being made in this thread. The first is all front wheel drive cars understeer (or are inclined to) I do not agree. A front or rear wheel drive car can be set up to oversteer. What is different about the two setups is how the driving power effects the handling.
If a car is travelling around a corner in a steady state condition (ie not accelerating or decellerating) the handling balance will largely be influenced by the chassis, and the wieght distribution. If in this condition, cornering at a speed where one tyre is at the highest point on the grip curve, they car will respond differently to an increase in power depending upon whether the car is rear wheel drive or front. But how this effects it is not as clear cut as one might think, and will largely be dependant upon the wieght distribution, and general handling characteristics. But one must remeber it will be the drive who has put himself in such a position.
Whether one trails the brake into a corner or not, and the time taken between blending brake into throttle mid corner will all effect whether a vehichle understeers in a given situation.
Giving too much throttle out of a corner in rear wheel drive will obviously increase the tendancy for oversteer, whereas visa versa will be true in a front wheel drive car. But how each car recovers from each condition will be strongly influenced by the car not just the drive type. If either drive system is too be deemed dangererous should we not all drive cars on high profile skinny tyres since they will not loose grip as suddenly as sportier modles?
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"Whether one trails the brake into a corner or not, and the time taken between blending brake into throttle mid corner will all effect whether a vehichle understeers in a given situation."
I believe everyone else was discussing road driving, NOT rallying techniques.
The previous generalisations were correct. All FWD will inherently understeer.
They can of course be made to do other things - by means of handbrake turns, etc., - but such has no place in in discussion of safety.
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props at the front - I was always taught this was a packaging compromise and not good areodynamically. basically trying to get weight lift point- thus giving inherently stable glider - i.e flies when engines fail.
If you look at the first flying wing the props were at the back and gave laminar flow over the whole wing - very efficient
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I know this is an old topic revisited, but you don't see too many FWD F1 cars...
I always thought it was done nowadays for ease of manufacture, as the assembled power train goes in as a complete lump.
BTW, I concur with Chris2's comment. I fly model planes, where 'pushers' are very popular and have good flying characteristics.
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I know this is an old topic revisited, but you don't see too many FWD F1 cars...
With the engine in the back, to drive the front wheels the prop shaft would have to go through the driver!!! Being serious the F1 car design is the pinicle of performance, packaging and handling, so it proves rear wheel drive/rear engine is the ultimate for speed, but it also requires very very very good drivers to keep it on the track at the limit. In fact for average drivers its dangerous! (ala porsche - only driver aids stop idiots killing themselves in that!)
I always thought it was done nowadays for ease of manufacture, as the assembled power train goes in as a complete lump.
Good point, makes sense, I have seen complete suspension, powertrain & engine being lifted into cars on the line - very quick operation.
BTW, I concur with Chris2's comment. I fly model planes, where 'pushers' are very popular and have good flying characteristics.
Ahhh much debate for nearly a century on this now. many pros and cons either way. If I recall correctly the deciding factor for props at the front was cooling air through the engine on the ground, and propelors are more efficient at the front, tho they do hamper wing aerodymanics.
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What about cars like the Saxo VTS, trouble with the 'drive it like you stole it crowd' who, if they get into trouble might easily panic and lift off the accelerator quickly in a bend. This would put it sideways (if not actually backwards?) into the hedge, if they're lucky and get away with a soft landing.
Having said that, unless the handling is set up specifically to let you get the car sideways, understeer is the norm on fwd cars and is what most people would be faced with at the limit and probably a useful assumption if we're discussing safety.
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Don't forget that a rwd car can suffer from lift-off over-steer too, generally power over-steer will occur first if enough power is being applied but it can still happen if enough speed is carried into a turn. Its not as simple as rwd = oversteer, fwd = understeer. There are plenty of rwd cars out there that will understeer for Britain!
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Don't forget that a rwd car can suffer from lift-off over-steer too, generally power over-steer will occur first if enough power is being applied but it can still happen if enough speed is carried into a turn. Its not as simple as rwd = oversteer, fwd = understeer. There are plenty of rwd cars out there that will understeer for Britain!
Quite true Tony! I used to compete against one driver who deliberately used to set up his Escort to understeer on the basis that this is a more stable condition.
He then mainly used to use the brakes in order to deliberately unbalance the car to get it sideways into corners, but was not then fighting to stop it going more sideways because of the basic setup.
He was just a shade quick[1] in case you wondered.
[1] Understatement of the century. No names but you will have heard of him even if you don't follow rallying.
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"Whether one trails the brake into a corner or not, and the time taken between blending brake into throttle mid corner will all effect whether a vehichle understeers in a given situation." I believe everyone else was discussing road driving, NOT rallying techniques. The previous generalisations were correct. All FWD will inherently understeer. They can of course be made to do other things - by means of handbrake turns, etc., - but such has no place in in discussion of safety.
But if you do not outgun the tyres in a corner, why should a front wheel drive car inherently understeer? It would be quite easy for anyone to take a front wheel dive car that understeers slightly, and fit a stiffer rear anti-roll bar and hey presto an oversteering car. Chassis engineers make decisions like how much anti-roll bar to use to tmake the car handle exactly as they please.
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>>a front wheel dive car that understeers slightly......
sounds like my Vauxhall Cresta with the knackered front shock absorbers and "guess what it's going to next" handling.
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"But if you do not outgun the tyres in a corner, why should a front wheel drive car inherently understeer?"
Obviously correct - understeer being caused by front wheels losing grip. Be it by too much welly, diesel on road, or (horror of horrors) braking whilst cornering.
"It would be quite easy for anyone to take a front wheel dive car that understeers slightly, and fit a stiffer rear anti-roll bar and hey presto an oversteering car."
Why? Why make a car intrinsically less safe?
Unless you want to MAKE it unstable, as in rally car setups?
Again, I repeat, what has this to do with road driving?
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"But if you do not outgun the tyres in a corner, why should a front wheel drive car inherently understeer?" Obviously correct - understeer being caused by front wheels losing grip. Be it by too much welly, diesel on road, or (horror of horrors) braking whilst cornering.
"It would be quite easy for anyone to take a front wheel dive car that understeers slightly, and fit a stiffer rear anti-roll bar and hey presto an oversteering car." Why? Why make a car intrinsically less safe?
That is the whole point! The engineers have made a car understeer beceause that is what is desired, albeit front or rear wheel drive. We agree understeer is a situation where the slip angles of the front wheels exceed that of the rear. The fact that the front wheels are driven will only have an effect upon handling when the car reaches the limit of traction offered by its tyres.
It has everything to do with road driving.
Rear wheel drive is only of use to people who want to go fast and experience the handling rear wheel drive can provide. I thnk many manufacturers would be hesitant about going back to rear wheel drive because of its innefficiency over front wheel drive. Fuel economy would decrease.
I was jsut trying to say cars dont understeer just because they are front wheel drive, many other factors are at work. Front or reear wheel drive just changes the way the car behaves in response to throttle input as you appraoch the limit. Unless you want to MAKE it unstable, as in rally car setups? Again, I repeat, what has this to do with road driving?
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hmm
well I\'ve driven a series of BMWs, Granadas,Volvos, Jags and Mercedes.. and Minis, Audis, Fiestas and Rover 800s.
Stoke on Trent - a city built on hills - i is impassable with RWD in snow. A 3 series BMW is a deathtrap with summer tyres fitted.. - winter tyres are a different thing.. but who fits them?
Stoke on Trent - a city built on hills - is impassable with FWD in snow. Because of all the RWD cars stuck !
In normal circumstances FWD is best for most average drivers.. me? RWD is great in normal weather.. and winter IF you winterise it..
I have had 3 spins in 38 years of driving: one in a Mercedes 260E, a BMW 3 series, a Ford Granada All in snow..and all rwd..
None in a an Austin A30 with winter tyres driving in Aberdeenshire with 6 foot snowdrifts when a student...(mind you it had no power.. but then it went through snowdrifts very well).
Food for thought..
madf
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Correct me if I'm wrong, but I was under the impression that under or oversteer was nothing to do with the tyres losing traction, but was caused by the wheel rim pushing outwards and taking a wider radius through a bend than the tyre and the tyre then creeping sideways to catch up, if you know whatI mean.
Known as the 'slip angle'
Isn't this why radials and cross plys could not be mixed on the same axle, because the more flexible sidewalls of the radial gave a greater slip angle than the cross ply?
But then I could be wrong. I quite often don't know what I'm talking about.
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You're right Tom. I've just put a set of tyres on my car that allow a greater "slip angle" than the previous set, this is felt in sensible driving and way before the situation you would call a skid.
The effect is to make the car understeer a little more to a normal driver in most conditions.
With respect to FIF and others it is a fact that FWD is far easier/safer for 99% of drivers 99% of the time. You only have to look at one of those police helicopter chase films and see a youngster in a 1300cc Astra holding off a powerful police traffic car for mile after mile of risky stunts.
If they were driving a RWD Escort from the 70s it would be facing the wrong way within minutes.
M.M
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I think MM is absolutely right. There is no doubt that "joyriding" only really became trendy because the vast majority of the FWD cars have idiot proof handling.
The original Golf GTI's massive success had a lot to do with it being very well behaved under stress.
Those old Mexicos and Capris would have put a large number of joyriders (and bystanders?) in hospital or worse.
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The original Golf GTI's massive success had a lot to do with it being very well behaved under stress.
Just as well it was really, the brakes were frighteningly bad when you first used them in anger, ok when you got used to the lack of stopping power!
Those old Mexicos and Capris would have put a large number of joyriders (and bystanders?) in hospital or worse.
specially the 3.0 capris - hairy or what, wedged one sideways under railway bridge once - the bridge was on a bend. Lesson 1 learned - it stays damper under bridges!
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No, slip angle is the difference between the direction that the tyre is pointing and the direction the car is travelling. If the sidewall of the tyre isn't stiff you can sometimes feel it distorting, but this isn't anything to do with understeer or oversteer.
Front tyres actually slip most of the time when cornering because that's how they produce the sideways force which steers the car. The slip angle is quite small in normal driving, 5 degrees or so and you can't really feel it, except for maybe a slight feel of the steering loading up? Wind on the steering a bit more and the slip angle increases, giving more grip and turning the car tighter. Of course there comes a point where you are at the optimum slip angle and from there on, the grip decreases, THAT's the point of understeer or oversteer when you feel that you can't catch it and more lock just doesn't help. Only less speed or a wider radius around the bend will bring it back.
Studies of different tyres show that crossplies (for the old fogies amongst us!) give quite an even level of grip versus slip angle, therefore the breakaway was always quite progressive. You never got much outright grip to start with and it fell away smoothly when it started to slide. Radial tyres give much more grip but tend to be a bit harsher when they give way, better driver ability is needed to balance the car on the point of sliding but most drivers can zip around in the safe zone for years. The gods of speed who drive racing cars on slick tyres have an even tougher time because they grip and grip and grip and suddenly let go, incredible levels of driver sensitivity are required to drive on the limit of adhesion but not pushing it over the edge.
Above is fact, my opinion is that some cars are fun to drive, safe to drive and a joy to barrel through the bends in. I've had the pleasure of seeing this in both front and rear wheel drive cars but also the misery of driving front and rear wheel drive cars which were awful! If getting a good driving experience was simple, all manufacturers would do the same, I'm happy that they have to keep trying to get it right.
Gareth
p.s. apologies for anyone who nodded off during the reading of this post.
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