The biggest problem is probably the front hubs. Do you have standard Sierra front hubs or 2wd Sapph Cosworth hubs? With the standard Sierra hubs it's worst. When lowering the car the front roll centre gets way too low making the car understeer and feel like it is falling over the front outer tire when cornering.


The biggest improvement I did to my 24v Sapph was replace the front hubs with 3dr hubs. The car rolled less, had less understeer and felt much more direct in the steering wheel.


Another thing is the rear beam. The standard rear beam makes the car understeer as well. Change it for a 6 degree beam and it will be better. Another simple change is the rear arb. I have a 21 mm one from a Scorpio 24v fitted.


My Sapph also has a BOA fitted and is on Ahmed springs and Koni shocks and with the above mods it handles very nice.