Well here's the answer for anyone still reading this thread..one of my favourite movies, actors and car chases...
The green VW was a famous continuity blunder as it appeared at least 4 times in the chase sequence. The two modern cars are re-makes of two classic cars that featured in the chase scene. Fantastic modern interpretations of muscle car styling.
We met a German couple with this car in Yosemite - "We only have ze small engine" - Only 3.5...!
The Challengers were like gold dust compared with Mustangs..which were everywhere.
Don't know what you mean about the Ford Si ...
...Sure, you rarely knew what the front wheels were doing, the ergonomics were a mess, the roof was a pain to raise and lower, we got 22mpg (but petrol was 52c a litre), the gearbox didn't respond well to small throtle inputs, I could go on and on.....but I forgave it everything when some souped up Jap coupe thing challenged us away from the traffic lights one day and the Mustang lit up its tyres and crushed its opposition - Like the Americans say - You can't beat cubic inches!