In the first mad max, there was still fuel flowing, it was pre-war. Big Bopper, the yellow Pursuit car, and max's yellow interceptor were V8s.. as was the Pursuit Special (black Falcon XB GT).. the yellow car driven by March Hare was a straight 6.
A lot of the vehicles in the post-war Mad Max 2 were ex-MFP vehicles - like the red Ford Falcon XA that gets written off by the Mack and the black Ford Landau with its carbs on the bonnet. Oh and Max's pursuit special of course. They were using what came to hand.. most of the Buggies are VW based, 4-cyl. Its only been about 3 years since the war and its implied that fuel is still to be found in caches or ruins in the wasteland, hence the huge long range fuel tanks of several vehicles (Humungous's fuel tanks are two 55 gallon drums!) Most of the time all vehicles are cruising to save fuel.. for instance Max only uses his supercharger twice in the movie, the rest of the time he's cruising. The only time they're really thrashed are during the intro, when Max gets the knackered Mack back to the compound (kin love that scene) and when Max tries to break out of the Vermin's lines in his newly fueled up XB. Which doesn't go so well.
Not that I was ever part of the madmaxmovies.com crew or anything
You must remember, above everything else, that it would be a bit of a lame francise if they were tooling around in Priuses or milk floats lol Plus old tech is easier to repair.
I always wondered where the Humungous found a refill for his nitrous..
