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Old 20th September 2007
DrSandman DrSandman is offline
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Default Is FWD really inferior to RWD? I'm not so sure!

I'm assuming that most of you have owned or at least driven all-wheel-drive or rear-wheel-drive cars. Have any of you actually noticed any performance drop with a front-wheel-drive car? I sure haven't.

With the exception of FWD understeer, none of the claims about FWD performance deficiencies make a heck of a lot of sense.

For example, the claim that FWD cars don't accelerate as well because the weight shifts to the rear seems like bunk to me. The car can only accelerate as fast as the drive-wheels can rotate on the asphalt and pull/push the car forward. In a FWD car, unless the weight shifts so far to the rear that the front tires skid under hard acceleration, all other things things equal, a FWD car should accelerate as fast as a RWD car. Only in the presence of skidding are the tires of a FWD car not pushing the car forward in the same capacity as the tires of a RWD car.

The claim that FWD cars don't accelerate as well in turns also doesn't seem very logical to me. When a car is turning, its speed is limited by the speed of its front wheels. (In a turn, the front wheels are moving faster than the rear wheels--the sharper the turn, the greater the speed discrepancy....hence the need for a front/rear differential in AWD cars). To make the claim that RWD cars accelerate better during turns seems unreasonable because it suggests two things: 1. Even though RWD wheels can only apply force tangentially from the circumfrance of the turn, they still manage to apply enough force to make the front wheels rotate faster (which means the car will move faster) and 2. that the rear wheels have better traction on the road during a turn than front wheels do. Neither of these seem possible.

When you look at a car from above making a turn, where is its pivot point? Precisely at the rear tires. Only if the car had 4-wheel steering would this not be the case (in 4ws, the pivot point is somewhere between the front and back wheels). Obviously, the sharper the turn, the more the rear tires pivot. The very claim that is made about FWD cars suffering in turns because of pivoting drive tires actually applies to RWD cars even more. Why? Because the front tires only pivot when the direction changes (i.e. going fron a right turn to a left turn, or a sharp right to a slight right). In all other cases, the front tires are rolling straight on their treads. The rear tires, in contrast, pivot any time the car isn't traveling in a straight line. Hence, the front tires theoretically should have more consistent traction on the road through turns thant he rear tires. More traction on the drive tires equals better acceleration.

Additionally, because FWD cars have the drive tires not only pivoting less, but actually applying force in the circumfrence of the turn rather than tangentially as the rear tires do (remember, it's the pivoting rear tires that make the car turn....without which the car cannot turn), the acceleration on a FWD car is in the direction of the turn.

This is conceptually difficult when you think of a car making a turn with a radius of 50m. Instead, try to think of a car at a stand-still making a turn with its front wheels turned all the way in one direction. You'll notice the following:

1. The front wheels rotating normally...in the direction of the turn.
2. The rear wheels rotating very, very slowly.
3. The rear tires pivoting significantly on the ground.

Now imagine, in this situation, which set of tires would do a better job accelerating the car? I'd say the front.

These three things will all occur in a larger turn, but to a smaller degree. Nevertheless, they will occur.

And as for handling? Well, what does handling have to do with which tires are driving? Even if it mattered, I'd say FWD cars would handle better....because they have better traction in nonlinear movement.

Last edited by DrSandman; 20th September 2007 at 03:18 AM.
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  #2  
Old 20th September 2007
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Quote:
Originally Posted by DrSandman
I'm assuming that most of you have owned or at least driven all-wheel-drive or rear-wheel-drive cars. Have any of you actually noticed any performance drop with a front-wheel-drive car? I sure haven't.
Yes, I have. It just means you haven't driven hard enough.

Quote:
Originally Posted by DrSandman
With the exception of FWD understeer, none of the claims about FWD performance deficiencies make a heck of a lot of sense.

For example, the claim that FWD cars don't accelerate as well because the weight shifts to the rear seems like bunk to me. The car can only accelerate as fast as the drive-wheels can rotate on the asphalt and pull/push the car forward. In a FWD car, unless the weight shifts so far to the rear that the front tires skid under hard acceleration, all other things things equal, a FWD car should accelerate as fast as a RWD car. Only in the presence of skidding are the tires of a FWD car not pushing the car forward in the same capacity as the tires of a RWD car.
This is basic physics. F=uN. The force of friction increases as the normal force increases. More weight over the drive wheels = more normal force, therefore, more friction and grip and less slip.

But you said it, accelerating hard will make them slip. Since when was hard driving unrelated to performance?

Quote:
Originally Posted by DrSandman
The claim that FWD cars don't accelerate as well in turns also doesn't seem very logical to me. When a car is turning, its speed is limited by the speed of its front wheels. (In a turn, the front wheels are moving faster than the rear wheels--the sharper the turn, the greater the speed discrepancy....hence the need for a front/rear differential in AWD cars). To make the claim that RWD cars accelerate better during turns seems unreasonable because it suggests two things: 1. Even though RWD wheels can only apply force tangentially from the circumfrance of the turn, they still manage to apply enough force to make the front wheels rotate faster (which means the car will move faster) and 2. that the rear wheels have better traction on the road during a turn than front wheels do. Neither of these seem possible.
If the front tires are using 100% of their grip to turn the car and you want to accelerate, you're asking too much of the tires and they're going to slide. It's as simple as that.


Quote:
Originally Posted by DrSandman
When you look at a car from above making a turn, where is its pivot point? Precisely at the rear tires. Only if the car had 4-wheel steering would this not be the case (in 4ws, the pivot point is somewhere between the front and back wheels). Obviously, the sharper the turn, the more the rear tires pivot. The very claim that is made about FWD cars suffering in turns because of pivoting drive tires actually applies to RWD cars even more. Why? Because the front tires only pivot when the direction changes (i.e. going fron a right turn to a left turn, or a sharp right to a slight right). In all other cases, the front tires are rolling straight on their treads. The rear tires, in contrast, pivot any time the car isn't traveling in a straight line.
This imbalance can create something called "throttle controlled oversteer", which allows control of the car's direction with the right foot.

Quote:
Originally Posted by DrSandman
Hence, the front tires theoretically should have more consistent traction on the road through turns thant he rear tires. More traction on the drive tires equals better acceleration.
Then when you accelerate, the traction magically shifts to the back!!!

Quote:
Originally Posted by DrSandman
Additionally, because FWD cars have the drive tires not only pivoting less, but actually applying force in the circumfrence of the turn rather than tangentially as the rear tires do (remember, it's the pivoting rear tires that make the car turn....without which the car cannot turn), the acceleration on a FWD car is in the direction of the turn.
True, but the tires have limitations in grip.

Quote:
Originally Posted by DrSandman
This is conceptually difficult when you think of a car making a turn with a radius of 50m. Instead, try to think of a car at a stand-still making a turn with its front wheels turned all the way in one direction. You'll notice the following:

1. The front wheels rotating normally...in the direction of the turn.
2. The rear wheels rotating very, very slowly.
3. The rear tires pivoting significantly on the ground.

Now imagine, in this situation, which set of tires would do a better job accelerating the car? I'd say the front.
If you drive like a grandma, like your example, this is true. However, you're talking about performance, and hard acceleration is going to spin the front tires into smoke.

Quote:
Originally Posted by DrSandman
These three things will all occur in a larger turn, but to a smaller degree. Nevertheless, they will occur.

And as for handling? Well, what does handling have to do with which tires are driving? Even if it mattered, I'd say FWD cars would handle better....because they have better traction in nonlinear movement.
With less steering feel due to a heavy weight bias in the front, increasing the need for power steering, the inability to invoke oversteer to counter understeer, and inability to smoothly transfer weight from front to back, just to name a few. Yes, this is a Saab forum and Saabs are FWD, but your logic says the laws of Physics don't apply to FWD cars. I say you need to drive harder and then come back with your new findings.

Last edited by timmehhhhhh; 20th September 2007 at 06:38 AM.
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  #3  
Old 20th September 2007
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Yep, all straightforward physics and mechanics (as in the mathematical kind of mechanics.)

Just looking at one case, we could compare, say a BMW with a Saab.

BMW like to claim the weight distribution is pretty much 50:50 front to back - let's make the same assumption with the Saab, and let's make everything else equal too, power available, tyres etc.

If we look at where the weight acts (F=ma) at standstill, we would see a straight line pointing down, through the centre of the car (a in this case is the gravity constant).

Now accelerate from standstill. The vector moves rearwards, let's say the line is 30dgrees from vertical now pointing towards the rear of the car.

Which car has the greatest traction available?

Well, the BMW has RWD, and the 'weight' of the car has now moved rearwards (I know it's not 'weight', but for the purposes of this it's going to suffice!) so friction between the rear (driven) tyres and the road has increased, so more power can be applied before the tyres lose traction.

The Saab, has FWD, but the 'weight' of the car has also moved rearwards, away from the driven front wheels, so u (friction constant) has decreased, which means less power can be applied before traction is lost.

1 up to the Beemer.

Cornering is similar.

When cornering, we are applying another acceleration to the mass (our car) - the car will want to carry on in a straight line and the only thing stopping it is the friction of the tyres on the road providing F (this is a centripetal force, but since F=ma, we must be accelerating - which we are, as acceleration as a unit has direction - and by definition a change of direction equates to a change in acceleration)

If we were to look at where the 'weight' of our car was acting as it goes around a corner, we would see that the weight acts towards the outside rear tyre of the car. Again the Beemer will be able to put down a little more power than the Saab, as the rear tyres have more friction and so again more power can be put through them. The Saab will simply spin the inside front wheel as there is very little weight acting through it, and indeed the nature of differentials is to put more power to the wheel with the least grip! (Note, this is where limited slip diff's come into their own, both on FWD and RWD cars - although on FWD cars it can make low-speed tight corners difficult)

That's 2 up for RWD.

Then there's the handling through corners. In a FWD car you are asking the driving wheels to do 2 things, provide power to move the car and provide directional control. The Saab will do either of these quite happily in most normal circumstances, however, push it around a corner and the front tyres will eventually lose traction and the front end will drift wide - understeer. This is a reasonably safe, benign condition - and, having played with my Saab a fair bit, you have to be really pushing it to get here in any serious form. It's a condition that car manufacturers like, because it is relatively safe for Jo Public - people understand that they've overcooked it and will ease off. The danger from understeer is if you are seriously into the understeer regime, panic, and back off the throttle totally - there is a chance that the front tyres regain their authority and 'snatch' you tighter into the bend causing massive oversteer - which in a FWD car is difficult to correct, particularly if having just a few seconds earlier you've been understeering and now the car's doing something Totally different - you quite often see this effect on those 'reality' Police chase videos - the crooks scare themselves around a bend and back off - promptly losing control!

In a RWD car, the natural tendency is to oversteer anyway - the front wheels are only being asked to provide the turning force, the rear wheels providing the power (yes there is sideways force on the rear tyres too, but...) - a pretty equal division of labour - and one, which if designed well, will mean the rear wheels lose traction before the fronts. The back end drifts wide, so tightening the turn (which further exasperates the issue) - now as long as you haven't entered the turn too quickly in the first place, the corrections are all perfectly natural - take a bit of power off and normal service is resumed - leave the power where it is and relax the turn using the steering wheel a bit and you are drifting sideways, which , with practice (balancing throttle and wheel) means you can drift the car around the corner (not great for speed, but great fun when you get it right - on a track OK ) and then relax and power out of the corner - OK, it sounds simple, but it takes practice (and I'm not that good) - but for driver satisfaction, it's a big tick.

I can't score the above, as it's down to driver preference and what the manufacturer intended the car to be, safe and relatively benign handling, or more 'sporty' and 'involving'.

Don't get me wrong, I know the limitations of FWD, but I do like my Saab and will be sticking with it for a while. RWD around here is all well and good during the summer, but up and down hills in snow I'll take the FWD anyday. When not accelerating hard, or where the surface has poor friction anyway (snow, standing water etc.) FWD can be your friend (OK AWD is better, but still...), RWD just doesn't have the weight over the wheels make the most of what little friction there is, and can't accelerate enough to get the weight to transfer rearwards enough either. (Not that you'd be wanting to accelerate hard in the snow anyway!)

Oh, there you go, one up for FWD.

ATB,

Phil
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Old 20th September 2007
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Quote:
Originally Posted by DrSandman
I'm assuming that most of you have owned or at least driven all-wheel-drive or rear-wheel-drive cars. Have any of you actually noticed any performance drop with a front-wheel-drive car? I sure haven't.

With the exception of FWD understeer, none of the claims about FWD performance deficiencies make a heck of a lot of sense.

For example, the claim that FWD cars don't accelerate as well because the weight shifts to the rear seems like bunk to me. The car can only accelerate as fast as the drive-wheels can rotate on the asphalt and pull/push the car forward.
That's right, but when the torque at the wheels increases such that the tangential force between the tyre and road overcomes the critical fricitonal force, the wheels lose traction. Let's say you're starting from a standstill, you start off steady to get the car off the line and then floor it, the centre of gravity immediately shifts further to the rear of the car as you accelerate, then boost kicks in and all of a sudden you have a lot more torque to the front wheels, exceeding the critical frictional force and resulting in loss of traction. This loss of traction would occur at a later time and to a lesser extent with a RWD because there would be more weight over the rear tyres at that point in time.

The only way to increase the critical frictional force is to increase the normal force pushing the two surfaces (tyre and asphalt) together. Therefore the RWD instantly has an advantage over the FWD during acceleration because the weight is biased toward the rear, and further acceleration only intensifies the effect.

Quote:
Originally Posted by DrSandman
In a FWD car, unless the weight shifts so far to the rear that the front tires skid under hard acceleration, all other things things equal, a FWD car should accelerate as fast as a RWD car. Only in the presence of skidding are the tires of a FWD car not pushing the car forward in the same capacity as the tires of a RWD car.
Let's say two cars, a RWD and FWD, are in a drag race at the local track. Both drivers are newbies with too much cash and both get off to a bad start and immediately lose traction. Even though there is loss of traction, the cars are still increasing in speed and therefore accelerating. Every little bit of forward acceleration is an advantage to a RWD and a disadvantage to a FWD, therefore the RWD will still have an advantage over the FWD even though the tyres on both vehicles are skidding; F=uN... N is greater for the RWD and therefore so is F.

Quote:
Originally Posted by MudMover
The Saab, has FWD, but the 'weight' of the car has also moved rearwards, away from the driven front wheels, so u (friction constant) has decreased, which means less power can be applied before traction is lost.
Just a technicality... u stays constant, hence being the friction constant. N changes.
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  #5  
Old 20th September 2007
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It all mainly comes down to driver, assuming both cars put out similar power, similar handling characteristics, and similar weight ratios.

You CANNOT drive FWD and RWD cars the same way. FWD cars typically benefit from trail braking.

I'm definitely not going to argue against that RWD is better in the long run, makes more sense in terms of transferring power through most of say, a road course or a drag strip. But in those instances where transferring power isn't the main goal (coming into through the middle of turns), then they're pretty equal. It's all about the weight transfer at the beginning.

Also, on the plus side, FWD is pretty forgiving. Understeer is easy to correct for the learning driver, and tends to not have the quality of "see-sawing" if overcorrected.

Basically, if you're the best driver in the world, and have a very well set up RWD car, pretty much no FWD car is going to keep up with you. For most people's applications on a middle class, or especially student budget, FWD is just fine.

That being said, i love me some RWD, but i'm also not convinced that FWD is the evil that everyone seems to think it is, and i'm pretty sure you guys are agreeing with me. After all, you drive Saabs. I will probably be driving a Saab very soon. I'm also in the process of accumulating parts to make the Celica into a very capable track tool, FWD and all.

tl;dr: I love everybody!

<EDIT>

Quote:
Let's say two cars, a RWD and FWD, are in a drag race at the local track. Both drivers are newbies with too much cash and both get off to a bad start and immediately lose traction. Even though there is loss of traction, the cars are still increasing in speed and therefore accelerating. Every little bit of forward acceleration is an advantage to a RWD and a disadvantage to a FWD, therefore the RWD will still have an advantage over the FWD even though the tyres on both vehicles are skidding; F=uN... N is greater for the RWD and therefore so is F.
Actually, depending on how bad the newbies muff up the start, FWD will have an advantage. RWD has the problem that if you start spinning, and keep on stuffing it, it will continue to spin. FWD, on the other hand, if you smoke the tires, you initially transfer the weight to the back when you first start moving. THEN, because you're spinning, and no longer accelerating as fast as you could be, the weight transfers back to the front, the goes back to the back when the car accelerates again. This is also how wheel hop happens. Basically, you can only launch so bad in FWD before it starts to correct itself. The weight will keep bouncing back and forth, front to back, until it completely grabs. In RWD, because the car will be spinning, DESPITE all the weight over the drive wheels, it won't stop spinning until the effective power levels are decreased, whether that be from getting off the pedal, the power curve not climbing as steeply higher in the rev range, or shifting to a higher gear to effectively decrease torque.

And trust me, i know all about muffed FWD starts. The CRX i have is a huge exercise in trying to control wheel hop as to not frag an axle. 1700-1800lbs, D16Y8, bolt ons, tune, and a 75 wet shot is an interesting thing to try to get down a drag strip with 185-width street tires.
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Last edited by concealer404; 20th September 2007 at 09:36 AM.
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Old 20th September 2007
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Everything the other commenters say is basically true, but that doesn't mean that FWD doesn't have some advantages of its own when you learn how to get the most out of it, like rotating the car at entry to a curve, then powering out of the curve, etc.
They just won an exciting 3 hour endurance race, beating Subaru, and this team has previously beaten BMWs. Check it out: http://www.jlracing.net/mosport070915.shtml
The same racing team also made this remark when racing at Shannonville back in June: "Shannonville's tight and twisty circuit actually favours front wheel drive cars with exceptional handling".
Caution: Some of their links only work in Internet Explorer because they use stupid MS backslashes (\). If using Firefox or other standards compliant browser, just replace the \ with the proper forward slash (/).
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Old 20th September 2007
final_evolution final_evolution is offline
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another big difference between fwd and rwd is the amount of power that can be applied reliably. In FWD the front tires do the breaking, pulling, and steering, while the back tires stabalize and baisicly assist the fronts. That is a ton of pressure on the same set of front tires.
I know Alfa Romeo fooled around with the concept of high HP FWD cars and came to discover that 300hp is about the max they could use and still have a stable reliable cars (i really wish i could remember the torque numbers because they are more important then the HP). So most cars you see with high HP are going to be RWD or AWD.
Now i guess with all the electro-gizmos they throw at cars these days all of this may be bunk.... but you still dont see production FWD cars with the kind of power you regularly see in RWD or AWD cars.
Also caveat that with enough body rigidity tuning you can essentially "balance" a FWD car to understeer, but once again you run into the problem that the front tires are taking all the stress.

FWD still owns in the snow though!
And saabyurk is correct on a tight course where RWD cars cant use the straightline traction they get from being RWD, FWD tear it up. Just go to any auto-X or TLAC event and watch the speed of the FWD vs the RWD on twisties and straights.
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Old 20th September 2007
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All this talk is making me miss drifting in my old nissan 200SX....and yes, you can only drift with RWD. I kept that ride as long as i could even with a new baby on board but after a while I had to let it go as I needed more doors!

All I can say is I miss the 'feel' of RWD. Cornering feels good and smooth. Acceleration gives the correct 'pushed from the back' feeling rather than 'pulled from the front' feeling. It just drives nicer. A drivers car must be RWD (and not so much special electronics please).

Saying that Volvo's and Saab's need to survive the cruel winter snow. FWD excels in this, nuff said.

FWDs are also cheaper to manufacture, easier to assemble and thats a fact (though I can't remember where I read it from!).
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Old 20th September 2007
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Quote:
Originally Posted by VectorDan

Just a technicality... u stays constant, hence being the friction constant. N changes.
Doh!

I knew that really! No, really, I did!

I suppose though, we could end up talking about how u can change, once the wheels are spinning though, with a cushion of gasses, molten rubber etc. now being laid - but that's just getting silly

Phil
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Old 20th September 2007
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No matter what, I still prefer a RWD car for the fun factor; however, I still like the Saab with FWD. My wife drives an AWD...will be interesting to see how the new AWD Saabs perform.
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Old 20th September 2007
LaserRed9-3Aero LaserRed9-3Aero is offline
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Lots of good info here, but I'll offer my short and simple take on it...

I've owned a RWD Mustang, a 50/50 split AWD Subaru Impreza WRX, a FWD-with-AWD when needed SUV, and many FWD cars over the years, with my Aero being the most powerful of any of them.

Under *normal* driving conditions, dry pavement, I don't think there are any performance differences and very, very little in terms of driving characteristics.

But once you start mixing it up a bit, add some rain, snow, gravel, or some 'fun', etc, then they most definitely do differ in performance and overall characteristics.

IMHO, AWD is the most enjoyable of the three because you get the 'safety' of FWD with the ability to have 'fun' like a RWD when you want to, with better traction than either. For me, it doesn't get much better than Subaru's AWD system in the snow. AWD + snow + emtpy parking lot =
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Old 20th September 2007
Jubilee Vert Jubilee Vert is offline
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Try this link, it does a decent job explaining this.

Link to Fifth gear show
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Old 20th September 2007
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Of course FWD is not inferior to RWD. Both orientations offer advantages and disadvantages. FWD has HUGE benefits in regards to interior space and fuel economy, as well as winter driveability and "safe" handling.

RWD typically is more fun to toss about, but I'm sure all of us can agree that a Viggen is more fun to drive than a Lincoln Town Car.
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Old 20th September 2007
DrSandman DrSandman is offline
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You guys are forgetting a very salient point here.....

A very significant portion of the car's weight sits directly over the front wheels. So while your argument that weight shifts back during acceleration, there is still more weight over the front wheels than the rear wheels.
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Old 20th September 2007
SecondmessiaH SecondmessiaH is offline
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sorry sandman, but you're trying to disprove accepted driving science, rwd has better high-performance characteristics than FWD

thats not to say that FWD doesnt have its advantages (just ask any saab engineer): good poor weather traction, overall weight (lighter), simpler assembly, predictability for the non-performance oriented driver and a variety of other things really speak in fwd's favor
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  #16  
Old 20th September 2007
SnowgodCCR SnowgodCCR is offline
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Quote:
Originally Posted by DrSandman
You guys are forgetting a very salient point here.....

A very significant portion of the car's weight sits directly over the front wheels. So while your argument that weight shifts back during acceleration, there is still more weight over the front wheels than the rear wheels.

Yes, but the majority of the weight is still sitting over the front wheels in a RWD car.
The illustration with the vector diagram is definitley the best put forth here. I'll try to put it into english terms here:
You're sitting in your car at idle, you are being pushed/pulled in only one direction - down into the seat. Correct?
Yes.
You stomp the accelerator pedal, now you're being pushed back into the seat. This is because the inertial pull (previously only gravity, now it's gravity + acceleration due to the vehicle) has shifted towards the back of the car. Thus if you're vehicle were on a scale, the rear of the vehicle would now appear to be heavier that it was when the vehicle was at rest, because of the transfer of weight. The same physical laws apply to either drivetrain, but a RWD setup is better suited to take advantage of this phenomenon, as the transfer of weight effectivley boosts the traction of the rear wheels.

In addition, a tire (or anything) only has 100% of it's ability to use:
Your front tires are turning with 90% of their ability, so in a FWD car, you have 10% of your front tire's available traction left to accelerate or brake (oversimplified). In a RWD car, your front tires can be turning with 90% of their potential, while your rear tires maintain 100% of their potential, which can be used to brake or accelerate.
In a more real-world, less simplified version:
You're in a turn utilizing 90% of your front tire's potential traction, leaving 10% of those tire's potential to perform other tasks. This accounts to 100% of your front tire's potential. In the same FWD car, your rear tires are just stabilizing the turn, so let's hazard a guess that they are using 50% of their potential to do so. Meaning that they are being underutilized by 50%.
Same turn, RWD car. Your front tires are turning at 90% of their potential, and you're not on the skinny pedal or brakes. Your rear tires are using the same 50% of their potential to maintain the turn. But, since it's now a RWD car, you can use 50% of a tire's traction to accelerate, whereas in the FWD car, you were only able to use 10%.
FWD: 90% + 10% + 50% = 150%
RWD: 90% + 10% + 50% +50%= 200%
To make the above numbers make sense, think of the percentage symbols more as "performance utilization points".
Hope that that all made sense.
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  #17  
Old 20th September 2007
DanS DanS is offline
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Now put some snow on the ground.....

These are everyday drivers and not "track" cars.

I think the handling deficiencies of front wheel drive are offset by the positive adverse weather handling. Its easy to walk away from a BMW at a stop light when there is snow on the ground. The parking brake provides for some exciting rear wheel turning too.
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  #18  
Old 20th September 2007
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cse_20 cse_20 is offline
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Inferior as a global statement, I would say no.
Depending on the application, there is better.
But I only bought a SAAB because Sweden has the same weather we do!
AWD gives some people over confidence, and more likely to have an accident.
No snow, ice, slush, and whatever else can accumulate over the asphalte, it would be RWD all the way.

Regards,
CSE_20
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  #19  
Old 21st September 2007
MacDubois MacDubois is offline
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This is almost just like a VW board, except you guys are fairly polite. On a VeeDub board DrSandman would have been banished to "the land of exiled noobs, afraid to show their virtual faces for fear of another virtual reaming," and the thread would get posted up to and locked at about 30 pages in less than 18 hours for the sheer spectacle of it.

DrSandman, what have we learned?

I'm sorry to say that you can't argue with physics. And race cars aren't rear drive because of tradition; rally cars excepted, lack of traction is exactly why FWD is great in those conditions, although still generally at a disadvantage to AWD.

To really notice a difference you have to be driving stupid fast. Well you can notice a difference earlier, but you can drive around it. It's only when driving absolutely stupid fast that you are really going to notice a difference. (No the 3 miles over the river and through the woods to grandma's house doesn't count. Go to an autocross sometime)

I don't even know what to go after here. But I'm gonna leave you alone, mostly because there are just so many variables and differences within individual models that direct comparison is impossible. But I will say I always prefer RWD, based on power oversteer ability, traction, better weight balance, more predictable breakaway and handling.

final_
I will say FWD is not better on twisty bits, as some said. In organized racing/autoXing, FWD is given weight and other advantages to make them competitive. In Street-Mod FWD cars had a 400lb. weight advantage on FR and a 600lb advantage on MR & AWD...and still didn't win. (I autoX with the guy who trophied in his Scirocco last year, he gave up and runs STX in a RWD BMW now). Compare a miata with something similarly prepped and with the same hp/weight ratio and good drivers. I'll take the miata everytime. But again there are so many variables that it's impossible to compare.

jackchoo
The other thing. You can drift cars that aren't RWD. See rally. I have drifted FWD on dry pavement before, but the beam axle+short wheelbase on my golf makes it way twitchy, transitions are tough. And I don't mean E-brake sliding, but your 4 wheels braking traction neutral-ish slide. Not nearly as impressive as a long smoky RWD drift/power-slide though. AWD can pull it off...check it. http://www.autoblog.com/2006/09/26/v...tro-drift-car/ but then it also does sub-10sec quarters so they've got power to spin the wheels.

The reason I won't buy another FWD or AWD car (unless for dirt/ice racing) is because of low traction conditions. I can't stand FWD in the winter, get in trouble and you are boned. Get in trouble with RWD and you can usually save it, plus you can turn without needing the e-brake. AWD is great for deep snow, but that happens lamentably rarely and the even less forgiving breakaway sours me on it. I'll go back to RWD and snows as soon as I can...maybe get a c900 for rallyX
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  #20  
Old 21st September 2007
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TheRedBaron TheRedBaron is offline
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I'll second a c900 for rallyx

I didn't see one important thing mentioned (although i didn't read every single word) - which is that at high speed, in my opinion FWD is sometimes better in the corners than RWD because it is more stable - like how you can mat it when you're coming out of a turn earlier than with RWD without risking a wicked tailspin.
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