Originally Posted by Jesstzn

Your question would be better asked if phrased ;

Who has installed lowering springs ( and what drop ) with stock OEM shocks at low miles and experienced premature shock degradation or failure.

The same early failure comments were being made over in the Passat forums but prior to me installing 2" drop springs with stock shocks I asked the question phrased like that and didn't get one confirmed reply. Mine were installed at 8K and at 40K there was no evidence.

Failures that were happening were on high mile cars and the few that did happen were on shocks that were near the end of thier life.

It turned it into a hearsay wives tale.

Originally Posted by me

Stock shocks with Sport Springs : Yay or Nay?
08/03/07 at 00:40:42 Quote Modify Remove
I get asked this question frequently, and I have an answer. Nay.

Back in the mid 90's when I started with this import stuff, we did not have much choice. Lower the car with shorter springs. Usually, with shorter you get stiffer too. Both these factors will improve the handling of the car. The problems with lowering a car on sport springs with stock shocks are pretty significant though.

#1 Reduced Travel
The stock dampers are designed to work within a given travel range. The will stroke up and down as the car goes over bumps. This movement is needed to maintain a good, safe ride. By lowering the car you are actually moving the range that the shock is asked to work under. You are asking the dampers to do something they are not designed to do by working them in a range that is smaller than they normally do. And one result of this is "bottoming out." When the shocks compress completely they bottom out, and the car crashes on the bump stops. The causes the car to pogo and bounce over bumps in the road, drastically hurting the ride and performance of the car. It is highly recommended to use dampers that are short-stroke or short-case with lowering spring to maintain travel in the damper system.*

#2 Degraded damper life
Speaking from experience, dampers in import cars generally last a very long time under normal conditions. I have seen numerous Accords, Civics, etc go well beyond 100,000 miles with the original shocks only showing hints of softening. You know a shock goes bad when the car seems to float around like a boat as though the springs are allowed to oscillate freely. The shock/strut system is designed to match the stiffness of the spring and keep it in check. The spring compresses to absorb bumps, and it expands to maintain contact with the road over dips. The shock is there to keep the spring from exhibiting natural perpetual motion which would allow it to bounce up and down forever. The combination of lowering the car into a modified travel range, and making the spring firmer (disrupting the stock shocks/spring balance) combine to cause advanced wear in the shocks. A shock that might normally last 10 years now won't last 6 months under normal driving conditions. Here it is recommended that shocks be replaced in conjunction with lowering springs to better match the performance characteristics of the springs.**

#3 Perceived savings result in more costs.
Typically, the savings associated with installing springs onto stock shocks are counteracted by the need to later replace the shocks with new units, aftermarket or otherwise. If shocks and springs are replaced at one time the labor costs are combined into a single cost. Shocks will be needed sooner than normal, and the labor to install them with be paid twice; once when the springs are installed, and once more when the shocks are replaced. In effect, while saving money in not upgrading the dampers, you will just be deferring the cost that you will eventually need to pay anyway, and indeed paying more by paying for labor twice. Save if you gotta. Do the shocks at the same time as the springs.


So, that's my story. I'm stickin' to it.

Marcus


* Note that Tein coilover damper kits all have short-case dampers and are designed to work at reduced ride heights without bottoming. They provide ideal travel, ride, and handling characteristics, which we strongly recommend for street sports driving. These kits are also adjustable for a range of ride heights, along with options such as firmness adjustability and rigid upper pillow mounts.

** We strongly recommend either Koni (twin tube) or Bilstein (mono tube) dampers be used in conjunction with any aftermarket spring, soft, stiff, low, mild, etc. Koni Yellows have the advantage of adjustability to tailer them to nearly any given spring available. Bilsteins offer a mono-tube design which is an upgraded design over twin tubes which provide better driver feedback, response and accuracy.