Introduction

There are many different aftermarket shocks and springs available for your E34. Since this is such a reoccurring topic on forums, I decided to consolidate whatever I could find into one piece describing the different (more popular) shocks and springs that are out there. For the money and performance conscious, it's important to get the right suspension setup. Much of the information below are opinions expressed by the very knowledge E34 owners from Bimmerforums.com and Bimmer.info.

Springs

Vogtland
Vogtland springs have a highly progressive spring-rate which stiffens up very quickly. This allows for a good ride and good cornering, w/o a harsh ride. These springs are slightly softer then Eibachs.
Drop: 1.8" (45mm) front and 0.8" (20mm) rear
Price: Around $210
Where to buy: pure-motorport.com, FCP Groton

H&R
H&R are the hardest riding spring, very firm, best for racing.
Drop: 1.3” (33mm) front and 0.75” (19mm) rear
Price: Around $250
Where to buy: Turnermotorsport, shox.com, eap4parts.com, pure-motorsport.com

Eibach
Eibach are the second hardest riding. A good compromise if you like to be a boy racer on occasion. Slightly softer then H&R springs.
Drop: 1.2” (30mm) front and 1” (25mm) rear
Price: Around $260
Where to buy: shox.com, tirerack.com, bavauto.com

Bavauto
Notorious for being a little too soft and saggy. Many people have experienced bottoming out using Bavauto springs. Bavauto recommends using Bilstein sport shocks with these springs.
Drop: 1.5” (38mm) front and 1” (25mm) rear
Price: $200
Where to buy: bavauto.com

M-Tech
These springs lower the car without destroying the ride quality & are designed to work with the popular M-Tech sway bars.
They were on the order of $349 shipped for a set of 4.
Where to buy: bimmer.com

Ground Control
The Ground Control system's unique design allows for easy adjustment. Simply lift the corner(s) of the vehicle that you wish to adjust and spin the adjustable spring seat up or down to raise or lower the vehicle. Ground Control strongly recommends using these springs with Koni shocks.
NOTE: it looks like these springs have been discontinued for the E34, so get em while you can!
Drop: 0 to 2 ”
Price: Around $380
Where to buy: autocarparts.com, sportcompactwarehouse.com

Shocks/Strut Inserts

Boge/Sachs
Stock BMW shocks.
Price: Around $380 for a set of 4
Where to buy: bmaparts.com, bavauto.com, shox.com, autohausaz.com etc etc

Bilstein
Firm to very firm ride, great handling.
Price: About $440 for a set of 4
Where to buy: Turnermotorsport, Bavauto.com, bmaparts.com, shox.com

KYB
Supposedly an alternative to OEM Boge shocks. They’re quite inexpensive and good deals are available through ebay constantly. Opinions seem to differ on the quality of KYBs. Some people experienced a very hard ride after installing these. KYB >> Kill Your Butt.
Price: around $280 for a set of 4
Where to buy: shox.com, tirerack.com

Koni
The Koni product is adjustable and can provide both comfort and/or handling depending on your mood that day. The Koni's are adjustable from practically stock, to firm as Pamela's new boob job.....very firm.
Price: About $650 for a set of 4
Where to buy: shox.com, tirerack.com

Common Combos

Sachs kit
Ride is a bit rougher than stock, but still comfortable, and the car corners quite well, especially with upgraded sways. The ride is harsher, but by no means harsh. On the freeway, the setup is smooth and comfortable...you feel some bumps, but it isn't jarring. Overall a good compromise of firmness, lowering, and comfort.

Price: Around $700
Where to buy: bmaparts.com, bavauto.com

Bilstein sport shocks and H&R springs
I have a 92 525 with H&R Sport/Bilstein Sport w/ 3mm low profile spring pads and yeah it's a little bumpy over rough roads but for the most part it gives a real good "connected with road" feeling.

Price: Around $660
Where to buy: Turnermotorsport

Boge shocks and Vogtland springs
Boge OE and Vogtland springs make a good combination.
They are very progressive and are quite comfy even with 17" wheels, but certainly not like stock with 15" wheels. Drop is indenticle to Sachs kit, but both the Boge OE struts/shocks and Vogtland springs offer a lifetime warranty and are less expensive, the Sachs kit has a 1 year warranty.

Price: Around $580
Where to buy: See the above, don’t know who sell them as a package

Bilstein Sport shocks and Eibach springs
Bilstein Sports and Eibach Sports-no problems but a very firm ride-car handles great! Maybe a little on the stiff side.

Price: Around $700
Where to buy: See the above, don’t know who sells them as a package

Koni Sport shocks and Eibach springs
A lot of my friends have complimented me on how well
my car rides. The suspension is definitely firmer
than stock, however, not jaw breaking. It's a nice
sporty ride. For regular everyday driving, I have the
Koni's in the front set at 1-2 turns from full soft.
I feel at full soft, the Koni's give the E34 too
floaty of a ride.

Price: Around $790
Where to buy: shox.com

Koni Sport shocks and H&R springs
With the Koni's set one half turn from full soft the ride is pretty civilized on decent roads and that setting matches up nicely with the H&R spring rates.

Koni actually recommends that you run the shocks full soft and only adjust them to a firmer position when the shocks start to wear out. I don't think I'm that weak, but when I put all my body weight on one side on the car, I get about a 1/2" of compression that rebounds instantly. It definitely makes the car firmer and you feel more road bumps, the tradeoff being that you can take corners at a significantly faster speed. The car is definitely more responsive laterally. After 15,000kms (9,400 miles) of driving with this setup, I would definitely do it again.

Price: Around $800
Where to buy: shox.com

Ground Control Kit (with Koni shocks)
The ground control kit costs about the same ammount as the koni / h&r setup; it provides a 2-4 inch drop. the ride is considerably rougher than the koni/h&r setup yet it yeilds much better handling when properly adjusted. If the roads you drive on are very bumpy / rough, you may want to consider a different setup. Overall: maximum drop, insane handling, very stiff setup.
Price: $380 for the Ground Control Kit, around $650 for the Koni shocks
Where to buy: See the above, don’t know who sells them as a package. It looks like Ground Control has discontinued the kit for the E34.


How to install shocks and springs

Don't forget to read Mr Lowell's great write-up on how to install shocks, or strut inserts for the front, and springs.

Enjoy the ride!