Or more accurately, how quick ? On a 70 B-body in particular, how quick could one hope to run without doing any permanent damage (twisting) to your unibody ? Do not want a bar, possibly open to the US car tool frame connectors as they look almost factory. Even with those, how quick could one hope to run, 1.50ish 60's ?? Would also boxing in the front and rear torque boxes make much of a difference ? Lower radiator core support stiffening braces ??