Factual error: There's no way the gyro helicopter could carry 2 men and four jerrycans of petrol across a desert. It is only built for one person and would never lift off. And where would they put the second person and petrol anyway?
Factual error: Mad Max turns on his engine blower with a switch. The blower in Max's car is driven by a belt attached to the engine itself. The only way to turn it off is to turn off the engine. It is possible to put the blower on an electric motor, but turning it off would simply shut off the oxygen and fuel, both of which are pretty important in an internal-combustion engine.
Suggested correction: Switch-controlled superchargers are real devices, for example the commonly used Toyota SC12 and SC14. They use an electrically controlled magnetic clutch to engage or disengage the pulley. When such devices are disengaged (off), a bypass valve on the air intake redirects air around the supercharger via some extra plumbing. Also, fuel doesn't go through the supercharger - it happens below the supercharger stack as normal (in the carburettor or via fuel injection directly in the cylinder head), so that part of the entry is also wrong. For the Interceptor in the movie, it's true that the Weiand supercharger isn't set up this way. It's all fake for convenience - just a hollow shell with a regular carburettor inside. The switchable effect is simulated through the use of a small water pump connected to the front of the blower drive shaft, driven by a tiny electric motor under the hood. But there is no technical limitation to having a real supercharger controlled with a switch, just like Toyota's SC14.
Factual error: It's impossible for the Gyro captain's helicopter to land in the compound the way it did. Those type of helicopters can't hover like normal ones and have to land on runways due to their speed. It can't just land on the ground directly.