Looking back to the Ferrari F1 98…Just_a_fan wrote: ↑20 Jul 2023, 00:16…
You want the cars to be shorter - to do that means reducing some combination of wheelbase and front/rear overhangs. Reducing the front overhang naturally puts the driver's feet nearer to any point of impact and reduces the amount of crash structure length available to deal with the energy. That means both the front of the tub is more at risk and the forces applied to the driver will be higher - shorter distance to absorb energy means higher acceleration.
So the only sensible way to reduce overall length is by reducing wheelbase. That's where any changes should be made.
Front overhang was shorter (todays cars have an artificially elongated overhang to cater for the delta front wing), drivers were sat more upright (for some reason the FIA ignore their own ‘best practice’ seating positioning regulations from LMH & GT racing - overall height was still 950mm), fuel tank was 190L (now approx 120L plus battery volume - no net change), V12 engine, transmission was ahead of the rear axle (iirc).
Two big areas there where a length reduction can be achieved.
In theory 2026 cars will have less average power available to them (MGU-H gone, reduction in fuel volume), requiring less cooling - all of this has the ability to reduce mass.
As mass has been added to cars since 2014 more mass is required to pass crash tests (the tests use Force as the primary parameter), mass reduction in the cars would have a knock-on effect (less mass required).
As I suggested previously, an ‘unrealistic’ minimum vehicle mass would not be unhelpful, many teams went for lower weight & less power when KERS was first introduced. In many areas of the rules you MUST use could be replaced with you MAY use.