I had one of those bag of bolts for a short while back then and the "computer" was an absolute joke.
A feminised/Americanised ( actually the badly synthesised mutterings of a new Zealand actress ) voice that a Currah micro speech would have sneered at allied to totally inaccurate readings which bore no relation to reality ( according to the computer I once managed 355 mpg on a short town journey at a steady 147 mph as displayed) and a penchant for totally giving up the ghost along with the digital dashboard display after a while added nothing to the driver experience and the display a horrible shade of electric green!
I used to have nightmares over that voice, "aver-rage few-el conn-sump-shun, Trippp-diz-tanse."
I would guess the "computer" was about as powerful as the average abacus, not a fully functional one but one with say half its beads missing and that it's maths package was either based on the contents of an ZX81 issue one 550 ROM minus the hardware fix or something knocked up by Intel's pentium floating point division!
The normal Maestro was actually a decent runabout for the era and very economical especially the diesel.
Listen and weep!
https://www.youtube.com/watch?v=gH8orI8jdCA
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