4WD or RWD ?

vitamin · 4 Sep 2003, 16:56 (Ref:708214)

Hi,

Today I had a great discussion with one of my friend about 4WD and RWD vehicules. He was conviced that a 4WD machine would accelerate faster than a RWD one. I have to say I didn't agree with him. Now I ask you ; what would you choose, an heavier 4WD car with 300hp or a lighter RWD car with the same power ???

noise boy 2 · 4 Sep 2003, 17:39 (Ref:708262)

depends on the car, there is more parasitic loss in a 4wd drivetrain so the rwd has an advantage there. The other thing would be road conditions, on anything other than dry pavement the 4wd car would have the advantage. Robert

**Adam43** · 4 Sep 2003, 18:20 (Ref:708290)

How much heavier?

What are teh powers? 300hp. Is that a car with 50ph & one with 350ph, or 400 and 700.

And as noise said, is this on dry tarmac.

Perhaps an interesting (current) car for a discussion like this is the Audi in SPEED GT Championsip. (although I wouldn't class it as a GT car

).

vitamin · 4 Sep 2003, 19:18 (Ref:708338)

Take two cars, one 4WD and one RWD with the same weight and power specifications, we can say 300 hp for 1400 kg.
Can the 4WD run a 0-100 km/h better than the RWD because of his 4 wheels drive or is it too much penalized by his drivetrain loss ?

Es Nes · 4 Sep 2003, 19:58 (Ref:708398)

off the line, awd is best. just watch the speed gt and touring races. the champion rs6 and audi a4 just rocket off line making the other cars look like they missed the light.

billnchristy · 4 Sep 2003, 21:02 (Ref:708443)

Yeah i was gonna say that, just watch a Speed GT or Touring race and you will clearly see that the Audis out accelerate everything!!

noise boy 2 · 4 Sep 2003, 21:59 (Ref:708478)

I think that it would entirely depend on chassis set up. I bet that given the right set up that the RWD car would whip the AWD car in a quarter mile (the right set up being 50/50 shocks in the back w/soft springs, and 90/10 shocks in the front, plus a set of BF Goodrich Drag TA radials). Robert

Smokey 6 litre · 4 Sep 2003, 22:32 (Ref:708521)

many factors would influence this, especially weight diestribution, chassis and the weight penalty.
good question though.

**GTRMagic** · 5 Sep 2003, 03:21 (Ref:708694)

Take a standard road car like a Subaru Impreza.

A FWD road car has the potential to be faster because when you dump the clutch from a high RPM (not that I would know how to do that

) there are only one set of wheels to spin, and the car generally bites better.

The AWD version of the same thing has to light up 4 wheels, and the central diff arrangement... so will be slower.

Having said that, so the same trick in the wet and see which one is more stable

R32 Nissan Skyline GT-R Group 'A' AWD as developed in Australia by Gibson Motorsport were said to be capable of sub 10 second standing quarters with the right diffs on board, the right tyres, and an unsympathetic driver... strangely they never tried it

Es Nes · 5 Sep 2003, 04:28 (Ref:708713)

fwd = front or four wheel? front would be the worst because weight transfer would take weight off the driving wheels reducing grip.

GTV27 · 5 Sep 2003, 06:21 (Ref:708775)

Quote:

Originally posted by GTRMagic
Take a standard road car like a Subaru Impreza.

A FWD road car has the potential to be faster because when you dump the clutch from a high RPM (not that I would know how to do that ) there are only one set of wheels to spin, and the car generally bites better.

The AWD version of the same thing has to light up 4 wheels, and the central diff arrangement... so will be slower.

Don't quite know how to put this, but what the hell are you on? :confused:

The AWD will be faster - always. The minute gain that the FWD might be able to get from keeping the engine in its power band through wheel spin will be very rapidly diminished by the lack of forward motion that that very wheelspin results in.

Whereas the AWD version can either simply drive off the line, with acceleration increasing as the engine rises into its power band, or the driver can slip the clutch and keep the engine in its power band (results in bad smell and short clutch life, er.. or so I'm led to believe*).

Try watching a GTP start and see how quickly the Evos and WRX's get away from everything else.

(*GTV does not practice or condone such acts, well maybe once, but it wasn't his car, the owner was a dork and he was asking for it

)

GTV27 · 5 Sep 2003, 06:24 (Ref:708777)

in answer to the original question - I'd take the AWD car over a RWD car, everything else being equal. will admit though, the hooning posibilities are greater in a RWD car, but am really getting too old for that now

krt917 · 5 Sep 2003, 12:03 (Ref:709044)

As I understand it, from a standing start, or from very slow speeds, a 4wd will usually be quicker as traction is the most important thing. After that, as speed rises, traction ceases to be an important fact and other things. like torque, weight, wind resistance etc become the determiningf factors. Obviously, it then comes down to the specific cars involved (although 4wd cars tend to be heavier).