Well with regards to the Kilen rear springs I can tell you this
1) we have all had rear suspension tracking / tyre wear problems
2) on Fiat springs I had a full 4 wheel laser/computer alignment done with critical focus on the rear where all the problems are
3) after fitting Kilen rear springs I had the 4 wheel laser/computer alignment done again as I was expecting a different ride height which seriously affects both camber and toe on the GM multi-link rear suspension.
I was really pleased to find that the rear geometry was the same!
Fiat have tapered coil springs with given ride height
Kilen springs are not tapered but have idential ride height and do not appear to affect rear suspension geometry.
This is what I found but, as they say, "your mileage may vary".
1) we have all had rear suspension tracking / tyre wear problems
2) on Fiat springs I had a full 4 wheel laser/computer alignment done with critical focus on the rear where all the problems are
3) after fitting Kilen rear springs I had the 4 wheel laser/computer alignment done again as I was expecting a different ride height which seriously affects both camber and toe on the GM multi-link rear suspension.
I was really pleased to find that the rear geometry was the same!
Fiat have tapered coil springs with given ride height
Kilen springs are not tapered but have idential ride height and do not appear to affect rear suspension geometry.
This is what I found but, as they say, "your mileage may vary".