Why would a car-size airlock be required? A simple airtight hatch for the car to dock to (similar to a suitport) would work fine.
The first car on the moon was unpressurized because the program was a once-cancelled afterthought designed to fit into a spare cargo bay and unfold, with tight mass constraints. MOLAB was impractical because of the upmass required, not because pressurization wouldn't have been useful.
The first car on the moon was unpressurized because the program was a once-cancelled afterthought designed to fit into a spare cargo bay and unfold, with tight mass constraints. MOLAB was impractical because of the upmass required, not because pressurization wouldn't have been useful.