So I've melted my brain a bit.
Background...
Mk2 960/S90 IRS uses a transverse composite leaf spring, rather than the coil springs of the Mk1.
The Mk2 IRS comes with either:
a. Nivomat shocks and a soft spring; or
b. Normal shocks and a stiffer spring.
LOTS has been said about the possibilities and limitations of these rear ends, but this old TB thread is the most helpful that I've found:
http://forums.turbobricks.com/showthread.php?t=110342&highlight=coil
Basically what it comes down to is that if you want the usual lower & stiffer springs, the soft Nivomat spring can be combined with coil-over shocks for reasonable/good results. The non-Nivo spring stops the car being lowered at all, but you can stiffen the rear spring rate with coilover shocks. Also possible to shorten/thin down the non-Nivomat spring to make it behave more like the Nivomat spring.
Here's a couple of ideas that don't seem to have been considered/discussed, and I'd like some input.
1. Fit Mk1 trailing arms to the Mk2 rear end. The upper spring seat is already there in the Mk2 rear end.
2. Ditch the leaf spring entirely, and use either Mk2 trailing arms with coilovers, or the Mk1 springs. The Mk2 arms may need reinforcement, but whatever - shouldn't be too difficult either way.
Is there are reason nobody else seems to have though about these options?
Mk1
Mk2
Both, but not showing the trailing arms.
Mk1 upper spring seat on Mk2 rear end:
Random tidbit: Live axle 940 shocks are the same length as Mk2 IRS shocks.
