The amount or size of torsion bar required is directly related to how much stiffening has been done to the car including a welded up/reinforced K frame.

Project black n blue has a welded reinforced k frame and lots of welding underneath with hemi leaf springs, torsion bars with FF sway bars and qa1 shocks. It is lowered to the minimum ride height with no compromises and only uses a 26 inch tall 10 inch wide tire...and some how it eats SRT8 Challengers on the road course with ease...


Who is ahead of whom in the picture?????....
And btw both drivers are very good...