When you strafe and turn into the strafe you pick up speed. I don’t know what do about that.
Also turning too quickly slows you right down, how do I conserve momentum on turns?
I had “take momentum from side and add to forward” but that caused problems with strafing, were strafing would speed you up
The physics of F-Zero on the super Famicom (or Super Nintendo) and on N64 were not implemented as in a standard physics module like Unity’s one. Japaneses are known for favouring gameplay / manoeuvrability over realism. So chances are that to mimic F-Zero physics, you will have to move away from certain aspects of standard physics.