mmarshall

The Quattro is a good and proven system, maverick, and was the standard-bearer in the over-35K class until the Acura SH-AWD came along...see my response in earlier posts. Nobody, though, does it better, more simply, or efficiently, however, in the under-35K class than Subaru. They make a simple but effective system that has fewer moving parts than anyone else. I disagree with spwolf about it being less effective than other systems in the same price range or " newer " systems.

We have to give Suzuki credit, though, on the new SX-4, for having a driver-controlled switch that varies the system between 2WD and 4WD.....that is a first for a small car and car-based AWD system....and they do it for only $ 15,000 to start.

mavericck

Here ya go: http://www.youtube.com/watch?v=KdUpg8GkJcA

http://www.youtube.com/watch?v=z1995...elated&search=

rai

here is a test from car and driver to compare rwd v fwd v awd as well as snow tires:------>>>http://www.caranddriver.com/features...-traction.html

GSteg

iTrader: (15)

NICE! i remember they did this in the 80s when they were introducing the system.

mmarshall

Impressive, yes, but almost any good AWD system and winter tires can do that...especially with tire studs, though studs are illegal in some places.

mmarshall

A good article. I remember reading it in CAR and DRIVER when it first came out ( in 1999 ), but that article represents what is now 7-8-year old tire technology.

Today's all-seasons are as good as some pure winter tires were back then.

Mr Johnson

Alas this blanket statement isn't quite a blanket.

If you have an engine that can break the traction of the rear tires (most cars today can) then an AWD system will accelerate more quickly than a RWD. Don't underestimate the ability of AWD in conditions of low grip or high horsepower.

mmarshall

You don't have to sell me on AWD's benefits. AWD's weight and drag does take its toll, though. You don't get a free lunch.
But that's why I said...all other things equal. Most high-powered RWD cars today have traction control that controls rear wheelspin. FWD cars are the ones that suffer most on hard acceleration because the rearward weight transfer front-to-back on hard acceleration takes most of the car's weight off the front wheels.....where they will be prone losing traction and spinning.....hence T/C kicks in again.

Mr Johnson

I'm not trying to convince you of anything. I'm pointing out your "blanket statement" is utter rubbish.

Either all things are never equal in which case your argument is a non sequitor or else your statement is wrong in a significant portion of automobiles today and is therefore not much of a blanket.

Another non sequitor. If TC kicks in acceleration will be reduced.

Four wheels have more traction than two. You wouldn't get a Veyron to run the times it does if it only had RWD drive "All other things being equal". Heck even an underpowered AWD Ford 500 on snow or in the rain will outrun a FWD 500 which would go towards proving my case more than yours.

I hear turbochargers always reduce fuel efficiency too except when they don't.

mmarshall

I don't think you and I are discussing the same issue here. I was referring to performance on dry pavement, not slick surfaces, Yes, as you point out, slick surfaces are another whole ball of wax....so please don't say my opinions are " rubbish" in the context that I was using them.
And an AWD 500 will outrun a FWD 500 on slick surfaces for more reasons than you point out.......the main one is the rearward weight transfer of a FWD car on acceleration taking weight and traction off the front wheels in spite of the inherent nose-heaviness of the FWD design.

That is one reason why you almost never see FWD dragsters.

And as far as turbochargers go, they generally reduce fuel efficiency only when in use, supplying a denser air-fuel mixture. If you featherfoot a turbo and keep the boost gauge down you will see little if any difference in mileage over its non-turbo equivalent....though a gas-engine turbo, of course, in most cases will use more expensive premium fuel and cost more to operate even with the same gas mileage.

mmarshall

The Veyron has so much max power....... 1001 HP and 987 ft.-lbs. of torque.....that whether it is AWD or RWD it would completely overwhelm the tires if it didn't have other traction aids. Yes....as you point out, with RWD only it would be next to hopeless unless you had NHRA-grade competition drag slicks on the rear.