anyway to modify quattro power ratio beyond 60/40 to the rears? Doesn't R8 get more to rears?

STaSIS makes a center differential that allows a 4:1 ratio (80:20)
 

not sure if they have one for the S5 yet, but it's worth contacting them.

R8 uses viscous coupling, not torsen

^ 2nd

take out drive shaft that goes to the front axle
 

mmmn, spinning wheels

holy cow...
 

I know this is off topic.
but I just went through your pics.
[a new habit of mine]
Are you kidding? Someone installed NITROUS in an R8?
WOW.
Was that you?

TO keep us on target, anyone put nitrous in their S5???

Actually, that would give you a 1:0 ratio in the wrong direction
 

You'd need to weld up the TorSen as well, otherwise 100% of the power would go to the front diff.

Also known as VT (Viscous Traction) in Lamborghinis
 

The Lamborghini/R8 system is purely for performance aplications and not for foul weather. But it's capable of some sick drifting like in this video.<ul><li><a href="http://youtube.com/watch?v=M-pi3nu8kyo&amp;feature=related">http://youtube.com/watch?v=M-pi3nu8kyo&amp;feature=related</a</li></ul>

You need a better monitor...
 

looks like a p-chop to me :)

lol, thats an old old pchop