So which factors work in favor (and against) a longer car achieving better lap times?
I'll start with a simple list of what comes to my head, but I am sure I'll get a couple at least half wrong an miss many:
- More floor surface to generate underfloor downforce.
- More distance from the front tires to key aero surfaces, allowing for the turbulence to dissipate to some extent.
- More distance from the front tires to key aero surfaces, allowing for the turbulence to be easier to push outboard.
- More distance (cleaner flow) between airbox and rear wing.
- More real state to add air controlling elements.
- Possibility for a slimmer read end, allowing for a cleaner flow in the diffuser area.
- Less front/rear weight transfer under acceleration/braking.
- More space to move elements around to control the center of gravity longitudinally.
- More space to place things lower to control the center of gravity vertically.
- Is it easier to accommodate taller drivers?
- And finally, cheekily and very much second or third order: A few extra cm needed for others to complete an overtake.
- More weight simply to cover the length of the car. Even with a weight limit, this means less ballast to play with.
- Even more weight to maintain torsional rigidity in a longer car. Alternatively loss of rigidity.
- There is more floor length to seal to maintain underfloor downforce.
- Less extra wing angle with rake as the possible rake angles are diminished.
- Does one effectively tighten the corners by a few centimeters?
- Does one need to turn the wheels at a higher angle to achieve the same car yaw? does this disrupt aero?
- And finally, cheekily and very much second or third order: A few extra cm needed for you to complete an overtake.
I am discounting a lazier car for turning. Longer (lazier) is better in open corners and worse in tight corners, isn't it?