jr'sAudiA6

Let me understand the issue. If you are trying to make essentially a 90 deg. turn left or right at 30-40 mph the car understeers and of course you are trying to remain in your lane.
The nature of the Audi power train lay out is going to give you understeer and of course you are going to have body roll. I'm surprised this surprised you. After all the A6 is a sport luxury sedan. There are things you can do to reduce the amount of body roll and understeer. The handling of the car is also strongly influenced by the type of tires you have on the car. I have recently gone to running NITTO Motivos for my every day tire. It is a high mileage A/S tire and does not handle any wear near as good as the Michelins. I have to keep that in mind when driving certain roads in my area when I get a little frisky with my driving. They have reduced my turn/corner speeds probably by 20-25 mph maybe even more. The following describes what I have done to improve my A6 handling.

I have tracked my A6 now 8 times at 5 different tracks. Two of those track events was with a completely stock A6 with the 20" sport suspension. The car definitely does have oversteer but I think it is generally mild oversteer. I have used the Pirelli P Zero's that came with the car and recently Michelin Pilot Super Sport tires on the track. With the stock configuration I was really impressed with how it handled the first 2 track events I attended. That said I felt I could improves its handling even more so I had installed the Stasis touring suspension, which lowered the car about 0.75" with firmer springs and replace the rear sway bar with a larger 28mm sway bar. I also installed the Stasis 370mm BBK on the front and recently had the GIAC tune installed, thou the tune has nothing to do with handling. When I had the car at Willow Springs race track on the big track I had an instructor take it out, with me as the passenger. Now this instructor has driven my A6 before on this track when it was completely stock. When he drove it for a couple of laps he was amazed at how much better it was performing and in fact he said it performed better than an M5 he had driven at a previous event. This instructor drives a lotus and he is able to drive my A6 better than I can at the moment. When I looked at his lap times in my car he was 5 sec. faster than I was and he told me he was not even pushing it.

irenesbob

Sounds like the OP may have screwed-up tire pressures; certainly worth checking out if this has not already been done.

salvadorik

As per manual i have 36 PSI front and 33 PSI rear. I so tire pressures are ruled out.

salvadorik

Gentelmen, I understand I may be too picky and my opinion may not reconcile with yours. I did not intend to discredit giving unsubstantiated critisism to our excellent cars. It is far better in many other ways than its competition. Most reputable car reviewers gave C7 very positive reviews (car and driver - car of the year - for example).

Having said that it is clearly an Audi design here. C7 is I think (pls dont qoute me here) is 4 inch longer in wheel base than C6. Audi increased wheelbase to improve driving dynamics as they are aware of their Quattro requires Longitudinal Engine placement, which makes front heavier. Sport diff was developed precisely to mitigate this issue. I just really hope that in the future (as someone noted here) Audi will make this car more enjoyable to drive.

irenesbob

Not to drag this out any more than either of us needs to, but I think the standard/normal load tire PSI settings Audi recommends are quite low for any kind of enthusiast driving - not speeding/hot rod style mind you, just not an old fart style. I would suggest re-setting the pressures to either the max load setting or somewhere in between, then noting how the car rides and feels. I find that with my car although the factory recommends 32 front and 33 rear (or something like that) I actually experience a more comfortable ride with the max load setting of 35 front and 38 rear (I have the 18" wheels). The handling is vastly improved as well with the higher PSI. My experience is that the car does seem sluggish. pushes a bit (i.e., does not turn easily per steering input) and actually thumps more over irregularities with the normal load settings. Sort of like it feels when you drive with a flat tire. It might be worth a try.
In my case at least I am not disagreeing with your perception of things, but rather trying to suggest something that might be helpful in enjoying your Audi more. Good luck.

salvadorik

Thanks. I will try this and report back.

skipper2

I notice a slight difference in the A6 compared to my old 2005 5 series which has a 51/49 weight ratio. Prior to the 5 series my wife and I had a pair of 3 series BMWs which are 50/50. Both had batteries in the trunk.

That being said, my wife and I went to the BMW performance driving course in S.C. back when I purchased the 5 series in 2005. We put the cars through everything including races, drifting, skid pad and emergency braking. It was a blast. The cars handled great. They were M5s. You could also use the 3 series.

I tried to re-create some of the things we did there (no skid pad) in a large parking lot here and did notice that the A6 was a slightly nose heavy during the hard turns, however I think it would perform slightly better in the rain than my rear wheel drive 5 series if you power into turns with the front wheels pulling you through the turn. In the dry weather, yes a Porsche or a BMW may bet you better extreme cornering.

SmokingTires

I'd stay away from generalizations, such as "BMW" or "Audi". Each has in their line-up extremely capable sport sedans (BMW M3, Audi RS4, Audi RS6, BMW M5, etc.) There's a huge difference between stock BMW 525xi and BMW M5. HUGE! So huge, that I could barely tell the difference in handling between BMW 525xi (circa 2006) and Honda Accord. Now, the 2006 330xi (also stock) handled so much superior to 525xi, that I ended up buying it. It was a blast to drive (while I realize that M3 would be way better).

When I switched to A6 I had no such expectations of it to handle like the BMW 330xi. It's a much bigger, heavier and softer car. I am very happy with it, but I understand its limitations.

All-in-all, you gotta compare apples to apples (e.g. A6 vs 535xi) and avoid broad statements that describe the entire brand.

looking@audi

I don't think this would be called understeer in the usual definition of the term. You are essentially making a 90 degree turn at a traffic intersection. You're turning a quattro 2 ton automobile at a right angle at 30-40 MPH. The front tires are pulling and the rear tires are pushing. This is how all-wheel drive feels in this driving situation.

A smaller, lighter, and rear wheel drive car would feel significantly different. With some throttle input you can actually kick the rear end out slightly in the same situation.

Having said that, if you are struggling to control your car in that situation - you need to slow down and get more experience driving your Audi.

irenesbob

Just to drag this out a bit more I have a question/thought: To my knowledge, most or all newer BMW’s come with run-flat tires, while Audi’s do not. Run-flat tries have (by design) much more rigid sidewalls than non run-flat tires. I have heard and read that this results in a sometimes less compliant or less comfortable ride in cars with run-flat tires. I was wondering if the same stiffer sidewall helps run-flat tires to maintain better initial cornering poise (with the same degree of under- or over-inflation) as compared to cars with non-run-flat tires. It seems to me that since the Audi’s tires’ sidewalls flex more easily, maybe they give the sense of less crisp turn-in, etc. compared to BMW’s. Maybe I am way off base thinking this is possible, but I thought of it after seeing a number of the comments here mentioning BMW’s the posters have in the past or are still driving. Anyway, just a thought.