I'd argue suspension is what gets the 60. Traction and initial acceleration is what cuts it short. Just as an illustration, lots of fast cars leave on the converter well past peak torque. This is because they want to be deep in the revs to get max work as early as possible.
Clutch cars will control the clutch engagement to keep the revs up but without smoking the disc before it locks.
Suspension allows hookup to get the maximum traction your tires are capable of. Lots of gear is torque. A loose converter does let the engine rev more, but also generally produces more torque multiplication. There is a limit on that though.