ryoung

Nuts, I was hoping to learn something from replies to your post ... but nothing. We may be in the same boat, but I'll give you my thoughts after 3000 street miles in my S8 (no track time ... yet).

1. Wheels and Tires: The 245/45-18's Dunlop SP8000's are not enough for this heavy car; even the A6 4.2 has more tire. I've heard that a 285/40-18 on a 10x18 wheel will fit, but not with enough confidence to try it without first seeing it with my own eyes. A bit more conservative would be a 275/35-19 on a 9.5x19 wheel; but again, I'd like to see this on an S8 first (rear will be OK, but I'm unsure about the front). My fallback will be 255/40-19 all around on 9.5x19 wheels. The radius of all three sizes is within 1/8" of the OE tire. Whichever I finally select, the tire will be the Bridgestone S-03 Pole Position.

With the OE SP8000's on the street, I've upped front tire pressure to 40 psi, which has totally eliminated the front tires washing out under hard cornering. At the moment, rears are still at 32 psi, but this does result in a very very slight oversteer as you near cornering limits. If you're uncomfortable with any oversteer, up the rears to 36 psi, though this will probably result in uneven tire wear (wear in the center). Tire pressure for the track is to be determined.

2. Brakes: The S8 brakes are undoubtedly an improvement over those on an A8, but I am unable to activate the ABS on a dry asphalt road from 70 mph, even on a moderately steep downhill gradient. I begin to get an audible protest from the Dunlop's, but there's not enough brake to lock a tire. The situation will only get worse when I mount wider S-03 Pole Position's. I'm thinking about upgrading to the 2Bennett Stage 2+ A8 brakes. It includes 355 mm (14" vs the S8's 11.6") slotted two-piece rotors (the aluminum hat also saves considerable unsprung weight) with Brembo calipers in the front, -AN brake lines front & rear, and the rear 11" rotors are slotted but otherwise unchanged.

Also annoying with the OE S8 brakes is the VERY soft pedal. I've heard stories that the problem is flexing of the OE front calipers under hard braking, and surely the rubber hose brake lines don't help. Hopefully the Bennett 2+ brakes will solve this problem also.

3. Tiptronic: IMHO, the S8 Servotronic speed "sensitive" power steering is horrible. You've probably seen my earlier post "My S8 has too much power ...". If you fix this before I do, let me know exactly how you did it.

4. Motor: I haven't really started to give this much thought, yet.

BTW, I drove an A4 last week. The brakes were better but not great, and the steering was an order of magnitude better than that on my S8.

So ... how does this compare to your experience? Any other S8 owners care to comment also?