German Car Zone

Fascinating topic this. I've been doing some reading...

Interestingly, according to KM77 (their info is always nothing less than straight out of the manufacturers' press release manifests) the R-Tronic version uses 13.6L/100 km versus the manual's 14.6L! That's very interesting because the R-Tronic gearbox is simply an automated manual.

So what is it Audi gurus? Heavier flywheel/clutch plate in the manual to handle the "driver factor"?

Edit:

The wind resistance factor is also negligible. The RS4 has a drag co-efficient of 0.34 and a front area of 1.99 sqm resulting in a resistance factor of 0.68. This play the RS4 with 0.31, 2.17 sqm respectively giving a factor of 0.67 - only ever-so-slightly better.

We could debate the differences in the AWD systems until the cows come home... and it would be interesting to see where the RS4's AWD system is more efficient than that in the R8 - if at all...

Here are some nice diagrams showing the AWD and Engine layout of the R8.



Note the spindly, off-centre propshaft coming through the sump and the offset of the main propshaft angle to the front differential.


Gearbox internals showing main rear differential (which gets 90% of torque in static conditions) and how drive is sent to the front wheels.


This pic shows where the propshaft emerges from the sump.


This is the front axle with the viscous coupling ahead of the front differential. This VC can only send a max of 35% of torque to the front wheels


...and this pic shows the R8's complex exhaust and catalytic convertor arrangement

I'm looking for a nice plan view (overhead shot) of the S4/RS4 drivetrain.
If anyone could post it here it'd be nice for comparative purposes...