Does anybody here happen to know the installed height and diameter (at the spring perches) of the rear coil springs for 2003+ panthers? I recall the perch diameter both on the axle and the frame is smaller than the coil midsection. I would like to have some aftermarket springs made, but don't have this info. Don't have any rear coils to measure against either, but have air springs instead.
The air suspension works fine, but I need to significantly increase the spring rate as I am converting to torque arm rear suspension without the added "spring" of the four link binding, so what I have now won't work. Let's not do the air vs. coil argument, it doesn't apply here.
2004 Silver Birch Marauder 140K miles
Wilwood F/R brakes, Penske 7500DA shocks, Hypercoil 600lbs F and Grand Marquis R air springs, Addco tubular sway bars, Metco control & Watts, 31 sp axles, Stainless Works cat-back exhaust, Lidio tune, BFG KDWS tires