Sportline springs on standard shocks? Which spring brands?

james111333 · 25 March

Hi, I have been trawling the forum for info as my 2017 Superb has one snapped front spring and one snapped rear spring so I am faced with changing them all. I have determined that the standard springs are

5Q0 411 105 GM (Blue, Grey paint dots) for the fronts

3Q0 511 115 AL For the rears

I think it would look great a little lower but don't want to go as far as 30mm+ with lowering springs.

Could I just get the sport suspension springs for a subtle drop on standard shocks (that wont be being replaced) or are the sport suspension shocks shorter also from the factory?

If it is not a sensible option to fit the sport springs and I just go for replacements, are there any brands to avoid?

For example, the options here range from £22 per spring to £52 per spring. https://www.autodoc.co.uk/spares-search?keyword=5Q0+411+105+GM+

I was going to go with standard KYB springs as there is a great deal on ebay where they are 15% off and I also get a further 10% cashback. I have since read some horror stories about the brand based around corrosion and the springs being higher than standard which would be a disaster!

Should I pay a bit more and go for Kilen?

Thanks for any input, i've done my best to search previous threads but can't find anything specific to my particular spring codes and there are lots of threads about lowering sportline cars when the sportline height would be a perfect upgrade for me anyway.

Carlston · 26 March

15 hours ago, james111333 said:

I have since read some horror stories about KYB based around corrosion and the springs being higher than standard which would be a disaster!

I know someone who has in recent years fitted KYB springs almost exclusively to about 10 different cars. The cars have often done high mileage, yet without any problems...no corrosion, no breakages, and no incorrect ride height. Considering that the Scala is fitted with KYB shock absorbers out of the factory by Skoda, and is one of the biggest suppliers of car springs and car shock absorbers in the world, I regard KYB as a premium brand. KYB claim to be number four or five in the world. KYB claim to make their aftermarket springs and aftermarket shock absorbers at least as good as the ones they sell to car manufacturers for fitment to new cars.

The incorrect ride height problem will usually be people selecting the wrong springs. Many KYB springs (like most other aftermarket spring brands) are sold to replace more than one OEM part number, so these springs are often not a like for like replacement, but will often be longer and/or stiffer than the springs they are replacing. To avoid this problem, you need to look at the full list of springs that an aftermarket spring is being sold to replace. For example, KYB RA5331 rear springs are sold to replace just 3Q0511115AL and no other OEM part number, so should be an exact match

Sometimes I've seen a KYB spring that gives a specification that is at odds with the specification given by another premium brand, such as Sachs. This might be a 0.5mm thinner or thicker wire diameter. I would probably avoid this particular KYB spring. Aftermarket spring brands do often make mistakes in the specifications that they give, so sometimes it might be that the specification they've given is incorrect rather than the aftermarket spring not matching the factory spring that it's being sold to replace. However, I did hear of one car owner who fitted KYB springs that were shown in the specification (and therefore should have been avoided) as having a wire diameter 0.5mm thicker than it should be...and the ride height did end up a little on the high side.

There are lots of counterfeit springs being sold, so maybe the very rusty KYB spring was a fake. Why would KYB's very modern factories produce springs that weren't well protected against rust? Cheap Chinese springs will often rust, so maybe that "KYB" spring was actually a Chinese counterfeit. It's well known that China are the counterfeit capital of the world.

I've got a small preference for Kilen/Lesjofors springs over KYB because Kilen/Lesjofors are made in Sweden and are Europe's biggest manufacturer of aftermarket car springs. However, the final choice will often depend on how well I think the aftermarket springs will match the OEM springs. It's nice to see that KYB often (but not always) list the specification of their springs but Kilen/Lesjofors never do.

Whatever springs you purchase, make sure you take and record full measurements before fitting...such as weight, length, wire diameter, outside diameter, number of coil turns, and a photo. Then if you notice any problems after fitting such as incorrect ride height, and/or too soft or too stiff, you can investigate further with the knowledge of those measurements. It's also important to find out before fitting a replacement spring that it actually matches the specification that you think it should be. Sellers often get parts returned by buyers, and things can get put back in the wrong box. The easiest measurement to make is weight (if you have digital kitchen scales). I was once sent a spring that weighed more than twice what it should have...and of cause, it was the wrong spring.

You should be able to use sports/lowered ride height springs with the standard shock absorbers, because not only are they about the same stiffness...but they are only about 15mm shorter (based on unladen ride height). Eibach even state that their lowered ride height springs can be used with the standard ride height shock absorbers...and those springs will give a bigger drop in ride height than the Skoda sports/lowered ride height springs.

One problem with fitting lowered ride height springs, such as a 15mm drop, is that you may need to increase the stiffness of the springs to prevent bottoming out. This of course makes the ride harder, but because the standard ride height car is known to ride quite softly many owners will still find the ride acceptable. One way to bring the ride comfort back is to fit tyres with bigger sidewalls. So if you've got the hardest riding 235/40R19, then changing to 215/55R17 would make quite a difference. Here's an example of an all-season 215/55R17 tyre.

Continental AllSeasonContact 2 215/55R17 94V (Euro label B B 70dB)

https://www.camskill.co.uk/m140b0s8825p220589/Continental_Tyres_All_Season_Car_Continental_Conti_All_Season_Contact_2_215_55_R17_94V_TL_Fuel_Eff_%3A_B_Wet_Grip%3A_B_NoiseClass%3A_B_Noise%3A_70dB

Edited 26 March by Carlston

Carlston · 26 March

When changing from standard ride height springs to sports/lowered ride height springs you need to change the 70mm front buffer to a 55mm, and the 127mm rear buffer to a 112mm.

When considering the length of replacement springs, remember that the stiffer the spring the less it will compress under the weight of the car. For example, if you changed the below

3Q0511115AA rear spring to 3Q0511115AD you might expect the rear ride height to drop by 9mm by just comparing the uncompressed lengths, but when you take into account the increased stiffness of the spring the rear ride height might actually increase by about 3mm.

Standard ride height front spring

5Q0411105GM Length 315mm, Wire diameter 12.25mm

Sports/lowered ride height front springs

5Q0411105HE Length 278mm, Wire diameter 12.25mm

https://www.autodoc.co.uk/eibach/17876011

5Q0411105HF Length 282mm, Wire diameter 12.5mm

https://www.autodoc.co.uk/eibach/17876012

5Q0411105HG Length 287mm, Wire diameter 12.75mm

https://www.autodoc.co.uk/eibach/17875999

Standard ride height rear spring

3Q0511115AL Length 359mm, Wire diameter 12.5mm

Sports/lowered ride height rear springs