Suspension mismatch Bilstein B6 and OEM Struts

[bollitin]

I have purchased a set of Bilstein B6 (35-229872) to replace my OEM shock absorbers on a 2015 S3 8V, with original coil springs.

When I tried to install them, the OEM spring was too short and won't fit.

The OEM strut has this part number 5Q0413031FR.

Should I get a new pair (longer) of springs?

Is it better to fit B8's as those have a shorter fit? Aren't these too hard vs B6's?

Will my ride height be affected by any of these two options?

[MikTip]

Too short???

Dont fit??? In what way dont it fit?

The S3 springs are short to begin with...cause they are "sport" springs and its a design from the factory to reduce weight.

Did you buy Bilstein Sport shocks?

Did you assemble the B6 strut with the springs and upper bearing?

It all "fits" once the upper spring bearing nut is tightned down then once installed on the car the cars weight pushes down on the spring and shock.

The ride height to determined by the springs. OE springs = OE ride height.

[Tahoe3.0]

Shocks and struts don’t dictate ride height, your springs do

B6 shocks/struts will provide a pretty stiff ride, think of them as a heavy duty version of an “A” car’s stock suspension. I would recommend B8s for your car as they’re designed to allow for max travel with a shorter spring which you have with the S model. Both b6 and b8 will work but b8 will work better.

[bollitin]

Let's not discuss ride height for the moment.

My issue is that B6's were supposed to be a direct replacement of OEM shock absorbers for the S3. It was stated both by Bilstein and by ECS (where I purchased them).

B8's are for "lowered" suspension, I'm thinking it refers to after market lowered suspension kits.

I have the S3 OEM suspension, with the original shocks, but the B6's strut stroke (the space between the base plate and the top bearing) is too long for the coil springs. The spring is around 1 inch shorter than the space.

I'm wondering if this is a "sport" OEM suspension and the B6's are not the correct direct replacement. Should it be the B8's, with a shorter space for the springs, instead?

I haven't check the rear or compared with the OEM rear shocks, but I also suppose B6's won't fit.

[bollitin]

Too short means that the space between the base plate and the top bearing (assembled, with the nut tighten) of the B6 strut is longer than the height of the spring.

[MikTip]

OEM is Sach.

Does your S3 have the mag ride electronic shocks?

I have the Bilstein Sport shocks.
The S3 springs are Audi sport springs...lower than A3 springs cause the S in S3...aka sportline springs...

The Bilstein Sport shocks are approx 1 inch shorter which should take up the gap

[bollitin]

Yes, OEM part is Sachs, number 5Q0413031FR (it's been replaced by 5Q0413031HD)

My S3 doesn't have mag ride.

When you say Bilstein Sports, you're referring to the B8's, right?

35-229919 (front) and 24-229937 (rear)

The thing is ECS insists that my OEM part number replacement is the B4 or B6. It seems, their equivalency data base (coming from Bilstein) is not correct.

[MikTip]

Yes, OEM part is Sachs, number 5Q0413031FR (it's been replaced by 5Q0413031HD)

My S3 doesn't have mag ride.

When you say Bilstein Sports, you're referring to the B8's, right?

35-229919 (front) and 24-229937 (rear)

The thing is ECS insists that my OEM part number replacement is the B4 or B6. It seems, their equivalency data base (coming from Bilstein) is not correct.

Bilstein shows a B8 shock for the S3...

https://cart.bilsteinus.com/results?...58247122724642

I have B8's on my 2015.

[bollitin]

Bilstein shows a B8 shock for the S3...

https://cart.bilsteinus.com/results?...58247122724642

I have B8's on my 2015.

Thanks, I think I'm going for the B8's.

The thing was, Bilstein and ECS say those shocks are for cars equipped with "aftermarket lowering springs" and their own OEM replacement guide (even for the S3 and my specific OEM part number) is B4 or B6.

I'll try to get the B8's length information online and measure my current shocks to compare.

[therollex]

Hi I have the same issue. What did you go for in the end, B8 with aftermarket springs or B6 with OEM?