I will put money down that Utrasport and Sport are exact same suspension. How much anyone wanna bet?
The front sways are the same thing from sport through S4,even though they have different part numbers. The rear sways are the same on USP and sport but thicker on the S4.
The rest is the same from Sport to Ultrasport and NOT the same as S4, which is a heavier car.
I'll bet my life on it. Search the other Audi forums; it's been brought up and documentewd numerous times with part numbers and dimensions/spring rates and everything.

 

From search:
From the look of it 1BA is the stock suspension, 1BE is the sport suspension and 1BV is the S4 suspension build code. Since there is a different build code the suspension is different. How different? Well I have checked to see which parts are different from the stock and 1BE suspension and here is a list:

Front Axle:
- Front upper link arm
- Rear upper link arm
- bonded rubber mounting (link arm bushing)

These parts actually share the same part number just the revision number is different and I can't really tell what the difference is between them. The 1BA and 1BE are identical only the S4 suspension is a different revision.

- The front sway bar on the S4 is identical to the A4 sport suspension one (solid 29mm bar)
- The springs are identical, they match the 1BE suspension springs part numbers and weight codes.
- Helper springs are identical to the 1BE suspension
- The shock absorber is a different revision from the 1BE, it is most likely due to the extra weight of the V8 (V6 uses different shocks than the 1.8T also on both 1BA and 1BE)

Rear Suspension:
- S4 springs are identical to the 1BE springs.
- Rear stabilizer bar on the S4 matches the 1BE stabilizer bar (18mm)
- buffer (helper spring) matches the 1BE
- Shock absorber is a different revision just as the front one.
- Suspension arms are identical.

So there you have the official response if the suspension is the same or different.

From what I can tell they are the EXACT same suspension, they beefed up the control arms a bit to handle the extra weight of the V8 but that is about it, no true difference from the A4 sport suspension.

 

From another:
These are the items that are unique to the Ultrasport package for the 2004/2005 B6 A4.

1) 18" RS4 Style wheels (18x8")
2) quattro GmbH designed lower front and rear bumpers, side door wings, and rear trunk lid spoiler
3) air leather (perforated) steering wheel and shift ****
4) aluminum trim (some have brushed aluminum - maybe a 2005 feature?)
5) 6spd manual (2004 exclusive)

In order to get the Ultrasport package, the interior color had to be Ebony only.

The Ultrasport package used the same suspension that's found in the Sport package.

That's it for the North American Ultrasport package.

In Europe, it was known as the S-Line package which also included performance tuning upgrades to the engine as well as the other items listed.

Dealers have been known to make the USP "seem" like more performance-wise, but it isn't. Great looking body style and some interior perks, but otherwise, the same exact car as a sport.

 

The suspension is by Quattro GmBh. Whether its OEM parts thats another story. Its built by the gmbh boys.

 

I may be wrong but still sort of right on the gmbh.... but I was under the impression that the gmbh for B6 A4 was only on the s-line, which is the European version of the Ultrasport. Thestateside version of the B6has identical part numbers for every suspension piece between the Sport and Ultrasport. So, if the US version of USP does have gmbh suspension, then so does the sport, so in effect, they still are no different because the part numbers are identical.
And it also correct in saying that it is essentially the same as the B6 S4, as well, because only the rear sway andfront stabilizer bar is different from A4 sport/ultrasport to S4.

 

fahquad, thanks for doingthe research. That was my exact question.

So if I were to get an A4 with a sports package that has the USP kit for a much price than a USP then that would be a good deal since that's basically the same minus the rims. Assuming theRS4 rims are cheaper than the price difference. A redundant question but just to confirm.

What's a good price for the RS4 rims anyway?