Jocko, with his fully streamlined dragster, broke the mold for body weight being less important than drag, when he broke the track record years ago, and the streamliners became the norm. Doug Kruse, who assisted in building that first fully streamlined car, built bodies for over 100 cars after that event.
The big variable that came in was tire surfaces, which now literally glue to the pavement, and peel loose, giving the equivalent of much more weight on the tires, without inertia.
Aerodynamic wings that produce down force, providing artificial weigh, no inertia.
Streamlining is another factor.
Balance front to rear, that has all the weight on the drive wheels, and front wheels just dancing on the strip.
Small wings at the front axle provide the equivalent of much weight, to keep the steering effective, and countering the torque from the rear wheels.
Rear tires that 'grow' as the RPM goes up, raising the rear of the dragster, causing downforce from the entire body to increase down track.
Engines that produce power to weight ratios un imaginable then.
Engines so near the failure point that they are overhauled after each run.
Those are just the big items.