QP Suspension

[AndyG]

Help i need the forums collective knowledge !

Having run my 06 QP for just over 14 months now (had a 4200 before) and gone through the pain of a clutch replacement and then a gearbox rebuild in the same month (ouch) i have been enjoying the car to the point that i'm now finding the Skyhook ride and handling is not the best, i have also developed a slight knock on the rear suspension, the same on both sides to which two indi's and one main dealer can replicate, but not pin point it.

To date i have done the following:

1/ Damper top mounts both sides.
2/ Changed both rear dampers for good used.
3/ Bottom damper bushes.
4/ Anti roll bar chassis mounts.
5/ Drop links.
6/ Track control arms (Warranty re-call)
7/ bottom wishbone rubbers.
8/ New wheels 20" Tridents.
9/ New tyres.
10/ Geometry done twice.
11/ checked all ball joints to many times, and still cant find any play.

The handling of the car i feel is very twitchy and even after the geometry being done twice i feel it has bump steer from the rear, however on changing the rear dampers this seems a little better. The knock is there all of the time and can be heard rather than felt on the slightest of road imperfection, its worse on road joints ie the concrete section on the M42 near Solihull.

My questions to the forum are as follows :

1/ Has anybody had handling issues as described and what is the cure ?
2/ Anybody had knocking rear suspension on their QP and what was the cure?
3/ Does anybody know the part numbers for the Bilstein dampers as fitted to the 07 GTS and will they fit my 06 Exec GT (Eurospares were very vague when asked)?
4/ Can anybody recommend a good geometry center near Birmingham ?

Please help if you can, as i'm getting very disheartened !

Andy

 

[BJL]

Hi Andy,

Your GT Exec suspension was unfortunately not set up for the 20" wheels having their rebound and bump stop calibrated for the 19" with higher profile tyres ie 40 front 35 rear.
My suspension on my Sport GT started to knock occasionally on uneven roads but only did it in normal mode. Putting it in sport sorted it but was not ideal on less than purfect roads in Dorset.

My relosution was to change the whole lot for the Bilstein setup on the GTS. The thread is on here somewhere.

It transformed the handling to the point the car felt new and tight as if. The geometry was set to Neutral bias on the fronts with max camber on the rears and i increased tyre profile alround to 40 fronts and 35 rears Pzeros. The skyhook to me always felt jittery in normal mode and somewhat disconnected to the rest of the car and after driving the GTS I new what I had to do. I'm going to the Ace so might see you there.

 

[BJL]

Meridien did my conversion and Giallo are more than happy to do the same.

 

[Ewan]

I have a 2006 QP and thought about following the footsteps of BJL and having the fixed rate GTS dampers fitted. But having checked with Meridien, Emblem and the factory, it's not possible. You need a 2007 or later car to fit the Bilstein stuff.