How different is the AWD system in the R8?

[FSI_ooomph]

In Manila when they say a storm is coming a storm will really come. It gets really slippery here when its rainy. I am gonna get my R8 next year but I just wanna know if the R8's quattro AWD system will still keep me out of trouble even if it is rear biased.

Why are AWD cars with really close specs to it's RWD opponent (e.g. Porsche 911 Carrera S and Audi R8 4.2) somewhat slower in a drag race. And what do they mean when they say the AWD system will bog down?

[willyjp]

I'm no engineer, but I'll attempt some of your questions.

Audi literature says power distribution to the front wheels is normally 15% but can vary between 10% and 35%. Probably quite adequate for that "planted on the ground" feeling you get with other Quattro Audis in wet or slippery conditions.

My R8 driving experience is limited to a track day @ Infineon Raceway with the Audi Sportscar Experience. During some of the skidpad exercises before we went onto the track, it was interesting to see that efforts to provoke wheelspin on dry pavement typically broke all 4 loose at once!

From my dry track experience and what I've read, I suspect most of the owners will tell you that their R8's are solid as a rock in the rain. Of course,
all cars with wide performance tires need to be wary of hydroplaneing in standing water.

I think the "bogging down" on take-off from a standstill is, at least to some slight degree, a feature of ALL all-wheel drive cars, in comparison to otherwise similar cars with rear-wheel drive. There's just twice as much drive-line rotating mass to get spun up. Again, from my experience at Infineon in 6-speed manuals, the R8 doesn't seem to suffer much "bog" if you "launch" with
reasonably high revs. A rear wheel drive R8 would probably do 0-60 in 0,5 sec less than the real thing with awd. If drag racing is your thing, buy a Dodge Viper or ZR1 Corvette, not an R8. The R8 is built for driving, not straight line acceleration.

[ianerrid]

In Manila when they say a storm is coming a storm will really come. It gets really slippery here when its rainy. I am gonna get my R8 next year but I just wanna know if the R8's quattro AWD system will still keep me out of trouble even if it is rear biased.

Why are AWD cars with really close specs to it's RWD opponent (e.g. Porsche 911 Carrera S and Audi R8 4.2) somewhat slower in a drag race. And what do they mean when they say the AWD system will bog down?

4 wheel drive cars bog down because they have inherently better traction than a 2 wheel drive car. To get the spectacular 0-60 times the car has to be heavily abused, typically these times are obtained by putting very high revs and 'dumping' the clutch and getting the 'right' amount of wheelspin. Often in these attempts they get too much and spin the wheels too much and end up with a slower time, or they get too little wheelspin and the car 'bogs' down i.e. the revs drop below the wheelspin torque threshold and you have to wait for the revs to build again. The Porker being rear engined and rear wheel drive has inherently good traction off the line if you get the revs right.

[bz888]

From my experience, always drive the R8 as a RWD car.

[harrison]

Or...drive it like you stole it !!!

[Bodhii]

The AWD is easily superior to RWD or FWD in the rain, no matter how wet. But the element that you do control directly is what tires you use. If you have a serious Monsoon season, maybe use a pair of serious rain tires just for that season. Bon Chance!

[MikeB]

Aquaplaned last Friday in a flashflood at 80mph on M6 toll road. Not much traffic and I eased over but had next to no control. Was swiftly overtaken by a couple of BMW's with, presumably, narrower tyres. I am not sure winter tyres would have helped as we were just floating. Watch out!

[mad-dot]

Aquaplaned last Friday in a flashflood at 80mph on M6 toll road. Not much traffic and I eased over but had next to no control. Was swiftly overtaken by a couple of BMW's with, presumably, narrower tyres. I am not sure winter tyres would have helped as we were just floating. Watch out!

I've had this happen twice in mine. Scared the crap out of me! I wonder if it's the tyres, as I've read about Gallardo's suffering too, and they have the same boots ?

[harrison]

The R 8s' tires are so wide !! Is there a decent rain tire in these sizes??

[bz888]

Correct. I broke traction last night accelerating flat-out in 3rd on the motorway during some rain!!! Bit scary.

I think it's a combo of wide tyres, speed and aquaplaning. It's a good idea to keep speeds under 60MPH/100KM/H during heavy rain.

PS: Disable ASR and see how the R8 behaves in the rain. It's not a safe, simple to drive AWD A4. It's a smooth, progressive and fun RWD sportscar!!!