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Old 8th November 2007, 14:05   #16
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Originally Posted by ananthkamath View Post
Its not just about which wheels are driven. Its also about the overall balance of the car and the weight distribution. You cannot even get close to the ideal 50/50 balance that a typical RWD car offers in a FWD. That is what changes the equation.
I also feel that if its RWD it should be Manual transmission as this helps taking corners without lowering speed. the auto tranny is scarry.
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Old 8th November 2007, 14:36   #17
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I guess FWD cars are better---I recall an ad around a decade ago with a guy pulling a partly opened matchbox on a table with his finger (FWD), and pushing it from the back (RWD). He concluded that FWD was better.
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Old 8th November 2007, 16:20   #18
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Originally Posted by sbasak View Post
I often notice there is so much enthusiasm about RWD cars because of their superior handling characteristics.

I read about torque steering and over steering but does it affect if you are driving sensibly on public roads?
And how often that is "feelable" in normal day to day driving??
Your observation has been proved again - enthusiasm about RWD cars etc..!

To answer your very simple question: the difference is not "feelable" if you are driving sensibly on public roads, or in normal day to day driving. The rest is all been here done that, as you have seen already!
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Old 8th November 2007, 17:16   #19
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Originally Posted by ananthkamath View Post
You cannot even get close to the ideal 50/50 balance that a typical RWD car offers in a FWD.
50/50 weight balance is "ideal" only in BMW marketing literature. Real world experience differs, slightly more mass on rear would usually be better in real world conditions (both braking and acceleration). Then there's the other extreme of certain Porsches, and the cars' entire design seems to be motivated by fighting this inherently flawed weight distribution.

But of course, both 50-50 or a biased 48-52 are far more preferable to front weight bias, as long as the car is designed to fully exploit this character.

The role of suspension and chassis specifications etc cannot be underestimated in final handling behavior.
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Old 8th November 2007, 17:20   #20
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Originally Posted by anupmathur View Post
To answer your very simple question: the difference is not "feelable" if you are driving sensibly on public roads, or in normal day to day driving.
True enough.

At 7/10 or 8/10, the typical FWD cars like Accord are just as good as anything a driver might require, and will certainly be better than certain RWD cars in snow/wet conditions. (Electronic nannies to the rescue).
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Old 8th November 2007, 19:14   #21
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In flat out acceleration, the torque-steer from a FWD is annoying and all too evident. In spirited driving around the curves, its just too easy to differentiate the behaviour between a FWD and a RWD.

Of the two, I'd pick a RWD anyday anytime.
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Old 8th November 2007, 21:21   #22
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Originally Posted by SuperSyn View Post
50/50 weight balance is "ideal" only in BMW marketing literature. Real world experience differs, slightly more mass on rear would usually be better in real world conditions (both braking and acceleration).
When a car is sitting still the most ideal balance to have is 50/50. Period. When it is moving though, weight transfer comes into play and as we all know: suspension tuning IS controlling weight transfer.
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Old 8th November 2007, 22:09   #23
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Originally Posted by vnabhi View Post
I guess FWD cars are better---I recall an ad around a decade ago with a guy pulling a partly opened matchbox on a table with his finger (FWD), and pushing it from the back (RWD). He concluded that FWD was better.
I do remember that. It was quite baseless. Why, The matchbox in this case was more of a trailer than a locomotive, as it was being moved on external force. Secondly a matchbox does not have direction guiding capabilities a car has (namely the steering system).

This was articulated beautifully by someone very close by using a shopping cart example. The carts turn because the external force is making it turn. Very unrelated to the working principles of a self propelled automobile.
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Old 8th November 2007, 22:14   #24
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another thing you may notice is when you NEED traction, say a rainy day and starting form a signal uphill (or even flat), RWD will give you better traction unlike FWD which starts wheel-spinning.

on corners, I have seen a lot of the RWD fishtailing in rain. mostly because power to weight ratio is much more in US cars/trucks.
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Old 8th November 2007, 22:20   #25
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Originally Posted by vivekiny2k View Post
another thing you may notice is when you NEED traction, say a rainy day and starting form a signal uphill (or even flat), RWD will give you better traction unlike FWD which starts wheel-spinning.

on corners, I have seen a lot of the RWD fishtailing in rain. mostly because power to weight ratio is much more in US cars/trucks.
So true. There have been times when my car's swerved all over the road,when I'd start moving on an incline. Corners feel tight and secure,there's no beating that.
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Old 8th November 2007, 23:05   #26
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Originally Posted by 1100D View Post
I do remember that. It was quite baseless. Why, The matchbox in this case was more of a trailer than a locomotive, as it was being moved on external force. Secondly a matchbox does not have direction guiding capabilities a car has (namely the steering system).

This was articulated beautifully by someone very close by using a shopping cart example. The carts turn because the external force is making it turn. Very unrelated to the working principles of a self propelled automobile.
But it is true that FWD is much safer than RWD in most driving conditions... the reason why most car manufacturers moved to FWD from RWD.

Regarding oversteer in RWD cars, no production RWD sedan or coupe oversteers. The suspension in all the RWD cars are factory tuned to understeer. In sports cars though, it is different.
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Old 8th November 2007, 23:06   #27
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During normal driving no diff, when u actually floor the throttle u get to see the diff.
RWD is more enjoyable when u floor it, wish my car was RWD ...
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Old 9th November 2007, 00:55   #28
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Quote:
Originally Posted by Mayavi View Post
But it is true that FWD is much safer than RWD in most driving conditions... the reason why most car manufacturers moved to FWD from RWD. .
Agreed. Safer, yes (for the average driving population). Faster exit speed thru a corner, no.

Now in US most drivers do not speed on a turn, they speed on a straight, in this case makes no difference. Moreover most US RWD's pre-charger/300c era were softly sprung. So they do not represent the sporty nature of RWD. Some people actually enjoy driving on ramps more than driving on the interstates meant for boats. Most german RWD's are sporty, even under very non sporty clothes.

In my first post I had actually compared the E320 with the Acura TL 3.5. Both cars of similar power output. TL is Sport tuned FWD and my E320 had the sports suspension package optioned by the first owner. I guess that was a true comparison of FWD vs RWD OF adequate power.


Quote:
Originally Posted by Mayavi View Post
Regarding oversteer in RWD cars, no production RWD sedan or coupe oversteers. The suspension in all the RWD cars are factory tuned to understeer. In sports cars though, it is different.
I beg your pardon?!

Last edited by 1100D : 9th November 2007 at 00:58.
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Old 9th November 2007, 00:55   #29
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Originally Posted by Mayavi View Post
But it is true that FWD is much safer than RWD in most driving conditions... the reason why most car manufacturers moved to FWD from RWD.
Yes, FWD is much more tolerant to ham-fisted drivers, whose abrupt inputs can be lethal in RWD. But, that's not the only reason, FWD is also cheaper to manufacture than RWD so that also plays a part.

Last edited by iraghava : 9th November 2007 at 00:57.
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Old 9th November 2007, 01:02   #30
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Originally Posted by iraghava View Post
Yes, FWD is much more tolerant to ham-fisted drivers, whose abrupt inputs can be lethal in RWD. But, that's not the only reason, FWD is also cheaper to manufacture than RWD so that also plays a part.
Modern RWD with traction control, it does not pose as challenging to the drivers you mention.

The only point is mainly the flexibility of platform sharing and packaging (small external sizing) that the FWD offers and overall lower cost of production. The real benefit of FWD, contrary to what the manufacturers will like you to beleive, goes to the manufacturers pockets.

Last edited by 1100D : 9th November 2007 at 01:06.
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