If you are buying new shocks, I would recommend buying shocks that are designed to take into account the shorter spring. Lots of people reuse their old (standard) shocks with shorter springs but if you have the opportunity you may as well get a shock that is better matched. They have less chance of blowing because they are not operating outside their design window.
From Bilstein:
- Bilstein B4 - These are classed as a replacement damper. A few B4 variations exist depending on the vehicle application but these are all intended to replace the standard shocks fitted when the car was new.
- Bilstein B6 - A non adjustable sport damper which is painted yellow. The B6 damper is designed for the motorist that wants a sporty ride without lowering the car or changing the original springs.
- Bilstein B8 - just like the B6 shock absorber but shorter. These are only for use with lowering springs or where listed for vehicles with factory sports suspension. The are shorter to ensure the all important coil spring pre load as lowering springs are shorter than OE springs.
I had Sachs OE replacements and Eibach springs. Terrible, but that could have been because two shocks were blown, and they weren't actually that old. I now have Sachs OE replacement shocks and Sachs OE replacement springs. Probably should have bought B6.