C4 Avant Quattro- Suspension

[AA6Q]

Are there any users with this model that have a modified suspension?
~ I have a 98 A6 Avant Quattro. its kind of a rare breed in the states. Its a C4 chassis and most systems show the 98 as a C5.

I am currently looking for Springs & Shocks.
What I have found is that the 95 S6 Avant has some matching options

H&R Sports 29921 (300#f/330#r) aprox 1.25

KONI offers a sport shock that adjusts before install

Bilstein offers a Sport rear & a possible Sport front insert as well as HD

Eibach is discontinued & NLA

PSS9 are the only C/O's avail & still pricey even & cost.


What are others using on this application?
Pics? post em if u got em. TIA

[s6sputnik]

Are there any users with this model that have a modified suspension?
~ I have a 98 A6 Avant Quattro. its kind of a rare breed in the states. Its a C4 chassis and most systems show the 98 as a C5.

I am currently looking for Springs & Shocks.
What I have found is that the 95 S6 Avant has some matching options

H&R Sports 29921 (300#f/330#r) aprox 1.25

KONI offers a sport shock that adjusts before install

Bilstein offers a Sport rear & a possible Sport front insert as well as HD

Eibach is discontinued & NLA

PSS9 are the only C/O's avail & still pricey even & cost.


What are others using on this application?
Pics? post em if u got em. TIA

unless there is a large weight difference between the v6 in your car and the I5 in the S6 I would be looking at what those guy have done... here is a link to one guys S6 avant (he no longer own's it) keith.maddock.com

BUT WHY?

[AA6Q]

I ordered the H&R Sports & Bilstein Sports.
while doing research I discovered many P/N listing for the same models, etc.
Some for S6Q, S6, A6, avants, qauttros, etc. Yeah, this a big wt. difference in the spring rates & vehicle rates for these variations. Wagons vs. sedans FWD & Quttro, V8 & 2.2T, etc. Way too much mis information listed on lots of sites. I contacted my distributers for the facts.

Thanks for the link. That is a very nice ride he had for sale.
RE: Why?
Cause I want to~ The current PO had Monroe's on there, the rear springs are slightly sagging. The suspension is a sway-box compared to what I am used too. I like the lowered look. I know about suspension dynamics & the effects of roll center/lowering etc. I prefer a firmer ride. I drive much lower cars in NYC on a daily, dropping the A6-truck an inch will be hardly noticeable. Additional driver/vehicle control is always welcome.

before, install & after pics as well as height measurements coming be end of week. :) :thumbup:

[FrankA6]

make a cardomain account and get a hold of this guy and ask him, theres some more C4 A6's on cardomain.

http://www.cardomain.com/ride/2131203

[AA6Q]

make a cardomain account and get a hold of this guy and ask him, theres some more C4 A6's on cardomain.

http://www.cardomain.com/ride/2131203

I have an old one from my A2 16v GTI days. Way too many forums & accts to play on these days. Gotta keep i to a minimum.

I grabbed the Bilsteins from my warehouse & am awaiting the H&R spring delivery. Install will happen this week & I am going to take measurements, pics, install etc.

...and my Corrado custom tune for SC'er should be done early next week too :) This week sucks, next week should be much better car wise ~

[AA6Q]

Install went ok. Ran into a few issues. Some anticipated and others not.

The Bils Sports in the rear listed as a 12mm shaft top & OE on the non sport susp. is a 10. This I knew I had, but sports are 12mm & HD were 10mm. I wanted the sports.
So- I had to open the center of the rear bushings & create 2 new piston sleeves. Cut to exact size but from a 12mm tube as the OE 10 were too small.

I have before & after pics & install shots as well. The fronts went well. Quite the PITA to remove the entire assembly (heavy too). Everything here went as planned.

Thee fronts dropped aprox 1.5" for some odd reason the rears are slammed & lowered almost 3".

Since the Bils sports only have 1 groove for the circlip there is no adjustment here.
All PN's & packing slip/box/parts are correct.

There are 3+ options I have to correct the rears.
~ Flip the rear spring seat to raise the height.
~ install a 1.5" or so spacer sleeve to sit on the snap ring and the perch will rest on this.
~ machine a set of grooves into the shock body to add adjustability like other Bils. sport model have.
~ weld the lower perch at desired hight.
~ replace w/ taller springs.

I am opting for a SS exact fit sleeve to place around the tube (rest on ring) and raise the height to where the perch sits, therefore raising the ride height.

I'll have to check perch clearance on most of the above methods.

[AA6Q]

So after additional research I have found that most users just flip the rear lower spring perch to gain additional height/lift of the springs. I personally dont want this as my 1st choice. After digging into E K T A I have discovered that the entire rear suspension components are different on the 95/95.5 S6 Q Avant.
Being that I ordered a suspension for this vehicle, I want what is factory correct. Ordering the few (dealer only) bushings, perches, & hardware would have run well over $500 for a handful of nothing.

Option 2 was to order the machined riser collars offered by ECStuning.com . These are vehicle specific as this is obviously not the first time this swap/install & issue has happened.

I contacted Shokan for some quality used pcs. and most of the rear assembly will arrive here tomorrow so I can get this wrapped up correctly once & for all.

If for some reason this still does not yield the correct right height I am only out 1/5th of what the dealer was asking & I will resort to the very simple fix of the machined collars or flipped perch w/ my OE components.

Once I get some time I will upload & host the install pics, EKTA diagrams & PN's from the A6 & S6 to clarify the differences. I can not believe this hasn't been posted by anyone, anywhere else considering I had the car 2 wks , but its been out over 10yrs.

[AA6Q]

I received & installed the correct S6 hardware & bushing & perch components on my A6 rear. The end result was that it raised it about 3/4-1", but it still looked like it had some sag/reverse rake going on. As a last resort to get this completed this week so I could actually drive the car & stop chewing up my badly aligned tires I decided to flip the lower perch. This along w/ the S6 parts raised the car much more. It now has some forward rake and looks pretty good and well as functions 100%.
** If I reinstalled the A6 components w/ the flipped perch it probably would be perfect.

I may take 2 more attempts to get this absolutely exact and perfect.
~This would be to flip back to perch to the normal position & decide how many/much height I want to add w/ the ECS rings(they come in 20 & 13mm) I am thinking 2x 13mm would be perfect. 2x 20 would be too high, so maybe 20+13mm ?

or just put back the A6 components & add 2 20mm rings per side.

Lots of trial & error. I have a very cool mechanic that is working with me on this. The rear shock has been off & on (w/ removing the spring, etc ea time) more times than I can even count. Erick @ Albertos Auto Repair on Concord Ave. in the BX. is his family owned & run shop that has been there for over 20yrs. Really good mechanics, fair prices and good people. He owns a Corrado+BMW and works on quite a few euros from NYC.

I should have time to get all my pics/data posted tomorrow.

[AA6Q]

I got my car aligned quite well on a Hunter machine @ Rams Alignment on Northern Blvd. I have had mixed opinions of this place because the prices varies widely as did the quality og the alignments. Sergio was the tech today & he did a great job. He even asked me where I wanted everything set.

My RF inner Tie rod was frozen & some WD+heat & muscle worked it out. With the S6 top mounts/camber plates I was able to max out @ -1.6 camber. A simple fix to reduce neg. camber would be to widen the slots in the camber plates for more movement. For $100 total I got a nice alignment F&R & that included the tie rod struggle/wheel removal/end removal, etc. More than usual, but no waiting, fast work, done to my specs. Drove 110 miles tonight & it felt quite good on the road.
The Bils Sport & H&R are on the very firm side & are probably not for everyone. My wife doesnt mind and were both used to dodging NYC obstacles so its nothing new & certainly easier than my rado.

[AA6Q]

shows F&R stock ride height followed by pics of R&F profile.

stock & H&R 29921 rear coils side by side
F&R components removed from car
Rear installed with A6 rear components and how it sat w/ A6 components & perches as normal. An aprox 1.75F & 3"R drop was the result.

28.25"Front stock

almost 27.5 Rear stock


Rear profile stock


front profile stock


lifted on rack


old fronts



old rears


new & used strut bearings/mounts.


rear mounting points in well


rear stock w/ worn bumps


differences in rear springs/height. linear vs. progressive



Front components removed


standard A6 rear components and the perches as normal.

rear drop w/ A6 components & normal perches. 24.5" (almost 3" drop in rears)

Fronts dropped to 26.5" almost 1.75" drop


as it sat with A6 rear components and normal perches



S6 rear components


Here are the part numbers and the differences in the components can be seen in the diagram. A6 rear on left, S6 rear in middle and ?? on right.


S6 rear components installed w/ perches as normal ( no car pics as it was still too low in rear when we let down from lift. but it was somewhat higher than previous A6 components)


With S6 components installed & perches flipped to raise higher in rear. ( now has rake & it a bit too high. No pics of current setup on car yet.)




Modified by CorradoMagic at 1:52 PM 4-21-2008

[AA6Q]

as it sits now with S6 suspension(rear components) and perches flipped as in above last pic.







makes no noise, rides great. I may flip perch to normal & just get some riser rings in the future but this will have to do for this week.

I'll get new measurements tomorrow.

[AA6Q]

wnet & tried the last combination the other day. *(actually tried it before & it looked low when dropped from lift), but now it seems perfect.
S6 components all around incl. S6 rear mts. The lower perches in rear are in correct position & it sits great. The rear gap is smaller but thats standard as the front fender line is cut higher(optical illusion), however, the body line still rakes forward some & the car sits level.
With a ful tank, gear & passengers the rear may rake down some but I havent tried it yet. I would say the ECS 12mm spacers would be a perfect additional to make this 110% but as of right now, its staying put, is as supposed to be & done correctly using all S6 components.