Torsion bar size effect

Bigger bars are stiffer which will improve handling to a point, but ride will suffer with too much bar diameter. Sway bars will make a huge difference without impacting ride quite as much. 1.090 bars are pretty hardcore stuff, and used alone will ride rough and cause massive understeer. You need to think balanced package here. Try to find a copy of Mopar's "Chassis" book. There are other chassis performance books out there as well.

.890 T-bars, HD rear springs (non-lift), front/rear sway bars and good shocks will make your car handle pretty decent without shaking itself or you to bits.