Here's the cure for 156 V6 suspension woes
Having read a great deal on this site about the somewhat "under-damped" and "crashy" nature of the 156 V6 suspension on UK roads, I think I have the answer for you.
My experience is based on my own 1999, 156 V6 which has done 46,000 miles, is well cared for and whilst not used for track days etc, is very much driven as it was intended. It is a SP3 version un-modified.
I have had the car for about a year and have bitter sweet feelings about the car, I adore the sharp steering, the looks, the sound and pull of the engine, and the individuality of the car.
The suspension however is absolute ****e. No question as I have experience of loads of cars, and this is clearly the bitter part of V6 ownership. On smooth tarmac it is reasonable, however, on country lanes or any non billiard table smooth piece of tarmac the car wallows, creaks, groans, crashes and feels like it wants to skip off the road.
To put things into context I also own an older BMW 5 and despite my general dislike of BMW's (common/sombre/bland but efficient!) I can honestly say that the BMW handling is spot on when compared to the 156. Another league altogether.
So I had the suspension checked over by my local and trusted garage, and their conclusion was; no leaks in the dampers or obvious faults (apart from a worn rear bush duly replaced) - but just wear and tear expected at 46,000 miles plus the charcteristics of a car with suspension born bad.
With this news I was left with two options:- get rid of the car or keep it and modify the suspension. And boy am I glad I chose the latter.
A friend of mine referred me to an Alfa Racing Specialist in Sussex. A phone call to them and some "no bull****" advice led to the car being booked in for a thorough "going over" with the promise of revised suspension characteristics that would put a big grin back on my face.
To my amazement the cure was simple:- junk the original springs and replace them with Eibach springs. These lower the car by about 10m (irrelevant) but are more softer, more progressive and suit the heavy front end nature of the V6. Also replace all the dampers with standard V6 dampers (believe it or not!) as they complement the softer Eibach's following numerous tests carried out. Also replace the upper and lower wishbones which at that mileage are shot. Do not let anyone else tell you otherwise as they have such an effect on the stressed movement of the suspension. Finally a full geometry check and set up.
As you can imagine, I picked the car and hesitantly took it out for it's first run. I was dreading it to be perfectly honest as the "old" cynic inside me kept saying "you've spent a good few quid on this and it won't be transformed - you will be pleased but not blown away with the results".
No exaggeration - as I still have to pinch myself now. The car was totally transformed. Honestly it just drove like a completely different car. I still cannot believe how those simple changes could make such a difference.
Firstly the ride feels so supple compared to old. There is no wallowing or pitch at the front and the car just digs mid corners with a controlled poised feel. Nothing at all like the original set up.
Secondly there is no crashing and banging and the steering feels even sharper now with better turn in and balance. No doubt due to the new bushes.
The most amazing single thing is how balanced the car feels front to back. It feels neutral and not like the front does not know what the back is doing when pressing on not so smooth roads.
I have no doubt that the Eibach springs are the major reason for the change and whoever designed them clearly knew what they were doing and had researched the Alfa OE set up. They may be softer but boy do they work. Hats off to Eibach.
Other conslusions:- clearly Alfa parts wear out quicker than most other cars and thus if you love your Alfa then you need to replace suspension parts early to enjoy the driving dynamics of the car. Also and conversely, going for a harder suspension set up not always the best way to improve a car's handling.
Finally regular suspension geometry checks are needed as i am now firmly of the view that the 156 is very sensitive to set up and the crap UK roads are so bad that just a few pot holes or bump later you could have put your suspension settings out.
Hope this helps anyone interested in sorting out their 156 suspension woes. It certainly sorted out mine.
Cracking car is the 156 V6 when sorted properly. It's a shame that Alfa couldn't have done this in the first place, but hey, if it was perfect we would all bored silly as most BMW owners are.