In the original script this vehicle is one of the very few that managed to catch up with Max after he stopped to investigate the hanging of a family near the road. Only the fastest vehicles were able to pursue Max and the Landau was one of them. Rumors circulated that this scene had been filmed, but ultimately this claim was proved to be false.
Appearances on screen
The Landau first appears on screen chasing Max's Last V8 Interceptor along with Wez and a dune buggy. The Landau is driven by a "Bad Cop" but his passenger wears an old fashioned firefighter mask and wields a peculiar pneumatic dart gun. The same gun is later used by another Bad Cop to shoot Max through the roof of the truck. After the gun fires into Wez's arm, Max rams the Landau which crashes into the dune buggy. The Landau rolls and halts to a stop.
Surprisingly its wreckage can be seen at the gates of The Compound when Max carries Nathan in.
The Landau was based on the Ford Falcon XB series but shared its frontal appearance and luxury appointments with the P5 series Ford LTD limousine which was released at that same time . The Landau was marketed as a luxury model and not a part of the Falcon range at all. Produced from 1973 to 1976 was deemed a commercial failure. It was powered by an Australian built low compression (8.9:1) ratio version of Ford’s 351 cubic inch (5752cc) Cleveland V8 engine with a power output of 290 bhp (216 kW) at 5000 rpm. Transmission was a three speed “T-Bar SelectShift Cruisomatic” unit, allowing a choice of manual or fully automatic gear changing.  It had a 9 inch LSD and four wheel disc brakes, making the Landau and its similarly equipped LTD stablemate the first Australian-built cars with this feature. The Landau was discontinued when the new LTD was released in 1976 after a total production run of 1385 vehicles.
For the movie the Landau was equipped with a dually rear wheel setup along with reinforcing rod flares (with an extra wheel mounted on the boot). Black paint job decorated with totenkopf symbols on the doors and a skull on the hood. The grille was modified from the original 'flip' headlights to a wire mesh holding headlights. The front bumper is from a 1957 Buick Roadmaster.
The turbo setup consisted of WEBER 48IDA or 44IDA turbos turned sideways and connected directly to carburetors to appear side-drafted. In the movie this setup was obviously non-functional.
The concept of Landau's turbo system was borrowed from draw-through turbo setups.
The idea being that the air and fuel are sucked into carburetor first and then this mixture is compressed by the turbocharger and sent into the engine. The setup does not require an intercooler because the fuel and cold air need not to be cooled after meeting the turbocharger. Even after the turbocharger heats up it is still possible to cool the mixture by adding a methanol injection line that cools it before entering combustion chambers. Additionally this setup requires tapping into the oil lines to provide lubrication for the turbos. The throttle is controlled directly from the carburetors instead of being mounted on the engine itself. The setup on the Landau is obviously for show; a simplified version of a draw-through turbo that lacks oil lines, throttle controls and cooling injection lines. The general concept, however is valid.