No, it's not. B/E body torsion bars have a lower wheel rate for a given size bar. The bars are longer, and the LCA's are slightly shorter, hence the lower wheel rate. The 1.12" FFI bars on my Challenger have a wheel rate of 270 lb/in, the 1.12" FFI bars on my Duster have a wheel rate of 300 lb/in.
The B/E bodies also had more "anti-dive" built into their suspension geometry, so although all the parts look pretty much the same, there are some significant differences.
