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Old 12th March 2010, 00:45   #241
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I did not care for this thread until about three days back. Hardly made a difference. Now it's RWD all the way
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Old 12th March 2010, 08:01   #242
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I have a very basic question. Can any one elucidate the difference between AWD and 4WD, or are they same. TQ
Basically AWD is partial 4WD. What it does in most cases is that it has the ability to send power to all 4 wheels if a slip is detected (your friction changes from rolling friction to sliding friction). A 4WD vehicle is mostly geared towards serious off-roading or towing duties and has locking differential(s) with which you can manually switch from 2WD (mostly RWD) to 4WD.

Having said that, there are many different types of AWD systems in the market. The cheaper ones are mostly FWD by default with a computer controlled centre differential which can instantly send some torque to the rear wheels in case of a slip. Some are even known to use their Stability Control system to brake the slipping wheels and market it as an AWD system. The RWD based AWD systems do the same thing but in the opposite direction (e.g. Mercedes 4Matic, BMW, Chrysler 300 etc.).

Audi and Subaru are the only manufacturers right now who have a true AWD system on some of their vehicles. They have a full time 50:50 front to rear torque split at all times with the ability to transfer more torque either way in case of a slip. The centre differential becomes very crucial in these AWD systems, and a torsen (torque sensing) differential used by Audi is known to yield better results for performance driving. Subaru uses a viscous coupling type centre and rear differential which is geared more towards off-road use (maybe comes from their rally heritage). In the Impreza STi, Subaru uses friction plate/dry clutch type differentials which are even better than the viscous couplings.

Last edited by sujaylahiri : 12th March 2010 at 08:05.
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Old 12th March 2010, 14:50   #243
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Originally Posted by sujaylahiri View Post
Audi and Subaru are the only manufacturers right now who have a true AWD system on some of their vehicles. They have a full time 50:50 front to rear torque split at all times with the ability to transfer more torque either way in case of a slip. The centre differential becomes very crucial in these AWD systems, and a torsen (torque sensing) differential used by Audi is known to yield better results for performance driving.
Except on the RS6 and RS4, Audi use the the Haldex system. Haldex traction normally sends about 90% of its power to the front wheels and if there is slippage detected it will decide how much to distribute. That the reason most TT drivers wonder why their front tyres wear like FWD cars. Audi only use their Quattro technology on the RS4, RS6 and now the R8's. If i remember right the Haldex system is also based on a coupling system.

Haldex Traction systems are also used on Freelanders and Saab's.

Last edited by Samir Taheer : 12th March 2010 at 14:52.
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Old 13th March 2010, 23:40   #244
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Except on the RS6 and RS4, Audi use the the Haldex system. Haldex traction normally sends about 90% of its power to the front wheels and if there is slippage detected it will decide how much to distribute. That the reason most TT drivers wonder why their front tyres wear like FWD cars. Audi only use their Quattro technology on the RS4, RS6 and now the R8's. If i remember right the Haldex system is also based on a coupling system.

Haldex Traction systems are also used on Freelanders and Saab's.
I knew about that already, that's why I said before "Audi and Subaru are the only manufacturers right now who have a true AWD system on some of their vehicles".

However, the Haldex differential is only used on the FWD based Audi A3,S3 and TT; because the engine is transversely mounted like a Golf (which is what they really are ). The RS4 and RS6 all use Torsen centre differentials as they all have a longitudinally mounted engine, like a RWD setup. Subaru uses the same setup as well, and that's why their AWD system is marketed as Symmetrical All Wheel Drive.
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Old 9th April 2010, 14:03   #245
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Even contessa is a RWD, yesterday i had the taste of high speed handling and the excellent grip while maneuvering in pin bend turns.. thanks to RWD. smoked out bolero, verna and others..
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Old 19th April 2010, 18:35   #246
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Yep sudhindhra whatever electronic nanny comes or AWD, Rwd is special and the control that one has is phenomenal.Awd may be safe and give more traction but still doesn't give the raw feel that RWD has.
(deathproof,contessa-nice match)
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Old 23rd April 2010, 01:42   #247
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Originally Posted by Sudhindra View Post
Even contessa is a RWD, yesterday i had the taste of high speed handling and the excellent grip while maneuvering in pin bend turns.. thanks to RWD. smoked out bolero, verna and others..
Smoked out verna?? I know verna's handling is way orf the mark even for a FWD, but its engine has some good punch and unless you all were driving on a downhill with multiple hair pin bends I somehow can't seem to figure out how the Conti smoked the verna. Or is it that ur conti isn't stock?
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Old 23rd April 2010, 12:03   #248
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Smoked out verna?? I know verna's handling is way orf the mark even for a FWD, but its engine has some good punch and unless you all were driving on a downhill with multiple hair pin bends I somehow can't seem to figure out how the Conti smoked the verna. Or is it that ur conti isn't stock?
--------------------------------------------------------------------------------

Its a stock conty. Even i know the performance of verna, however my conty had an edge only when we were driving in ghat section for almost 60kms.
The advantage i had is the confidence on my conty, less fear because of its sturdiness and the road grip knowing my car wont topple down.
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Old 23rd April 2010, 19:04   #249
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Or maybe the Verna driver was a novice while you are an expert ! Especially in hill driving !
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Old 24th April 2010, 10:12   #250
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^^ could be. Guess he was flooring to pedal too much at turns and was not able to control his car properly..
off topic: Isnt bolero 4*4 by default or is it only custom made?
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Old 25th June 2011, 13:50   #251
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Default Re: Front Wheel Drive v/s Rear Wheel Drive

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Originally Posted by Sudhindra View Post
Even contessa is a RWD, yesterday i had the taste of high speed handling and the excellent grip while maneuvering in pin bend turns.. thanks to RWD. smoked out bolero, verna and others..
Quote:
Originally Posted by Sudhindra View Post
Even contessa is a RWD, yesterday i had the taste of high speed handling and the excellent grip while maneuvering in pin bend turns.. thanks to RWD. smoked out bolero, verna and others..
Wow a 2ton 50-60 bhp car with hardly any torque to show for,& with chassis and suspension design from era of our grandfathers, not only out does a lighter (nearly half the weight), twice the bhp, and T-rex torque(as compared to conti) car, but smokes it.
Or may be verna guy wasnt even racing,he was saving fuel.
I know verna is not a good handler,but that is when it is compared to others on market today.
Verna is still better than a conti.
Hills and hairpins require torque asmuch as they require good handling.
I dont think conti is going to smoke even a bolero.
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Old 25th June 2011, 14:40   #252
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Originally Posted by Sudhindra View Post
Even contessa is a RWD, yesterday i had the taste of high speed handling and the excellent grip while maneuvering in pin bend turns.. thanks to RWD. smoked out bolero, verna and others..
IIRC, in the 90s movie "Yeh dillagi" there's a car chase scene in ghat roads where Akshay Kumar(or maybe his double) does some brilliant driving in a Contessa, to catch up with Saif.
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Old 25th June 2011, 14:40   #253
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Originally Posted by dustom_99 View Post
Wow a 2ton 50-60 bhp car with hardly any torque to show for,& with chassis and suspension design from era of our grandfathers, not only out does a lighter (nearly half the weight), twice the bhp, and T-rex torque(as compared to conti) car, but smokes it.
Or may be verna guy wasnt even racing,he was saving fuel.
I know verna is not a good handler,but that is when it is compared to others on market today.
Verna is still better than a conti.
Hills and hairpins require torque asmuch as they require good handling.
I dont think conti is going to smoke even a bolero.
Maybe but there is a sea of difference in the way both cars handle.
Though weighty and all, the Conti with it's independent suspension setup,RWD and almost 50:50 weight distribution can't be matched by the Verna,whatever stonker of an engine it has.
And i don't believe that handling of car's improve over the years,except maybe a period of 50-60 years.
An 80s BMW will still outhandle a 2011 model Verna.
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Old 27th June 2011, 10:08   #254
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Default Re: Front Wheel Drive v/s Rear Wheel Drive

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Originally Posted by dustom_99 View Post
Wow a 2ton 50-60 bhp car with hardly any torque to show for,& with chassis and suspension design from era of our grandfathers, not only out does a lighter (nearly half the weight), twice the bhp, and T-rex torque(as compared to conti) car, but smokes it.
Or may be verna guy wasnt even racing,he was saving fuel.
I know verna is not a good handler,but that is when it is compared to others on market today.
Verna is still better than a conti.
Hills and hairpins require torque asmuch as they require good handling.
I dont think conti is going to smoke even a bolero.
At first, conty is not a 50-60BHP, instead its 88BHP and 1800 CC with enough torque and effective handling around the corners, you have to drive it to believe it. This conty lacked power steering, still it was way comfortable to drive. New generation cars can outclass conty by miles on a straighter line, no doubt abt it, but the difference ends there. me and my friend could see that these guys(verna and Bolero) were pushing so hard on their rides struggling to keep them on road and had some close miss, and i had to do nothing except to just drive normally.
And to be precise, we were climbing uphill i.e from mangalore to Bangalore.
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Old 27th June 2011, 12:28   #255
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Originally Posted by Sudhindra View Post
At first, conty is not a 50-60BHP, instead its 88BHP and 1800 CC with enough torque and effective handling around the corners, you have to drive it to believe it. This conty lacked power steering, still it was way comfortable to drive. New generation cars can outclass conty by miles on a straighter line, no doubt abt it, but the difference ends there. me and my friend could see that these guys(verna and Bolero) were pushing so hard on their rides struggling to keep them on road and had some close miss, and i had to do nothing except to just drive normally.
And to be precise, we were climbing uphill i.e from mangalore to Bangalore.
@dustom_99 might have mistaken your conti for the 2.0DLX diesel, that had only 53 BHP.
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