No, the ford fiesta has a torsion beam rear suspension. By placing a torsion bar ON THE STOCK TORSION BEAM it reduced the lever arms.
http://www.tbperformanceproducts.com...s/IMG_3495.jpgIt did NOT have any other modifications done to it ie. lowering springs, sways, intake, exhaust, tires, wheels etc) As for the mazdaspeeds 3 second gain please go back and read the section on the the mechanical reasons why it occured. I am not saying the FRS will witness the same gains because we are working with COMPLETELY different platforms(fwd vs rwd, turbo vs NA) but it will have gains because we have already witnessed it!