Thanks DMJ. I did do a quick search, but put in Maserati bi-turbo. There were probably too many threads on 250Fs and the like so I didn't go through them all.
What I liked about Group A touring cars was the variety of machines entered, especially the class cars. Plenty of manufacturers bothered to homologate suitable (and not so suitable) cars but only Ford and BMW, and to a lesser extent Alfa Romeo were very serious about it back in 1987.
IIRC, just as oddball as the Maserati bi-turbo, was the Alfa 33 that turned up at Bathurst. It didn't have a snowflake in hell of being competitive with the best Toyota Corollas (9s a lap slower) but it added to the variety by just being there. So did the lone Alfa 75 Turbo (after all the factory cars were withdrawn) which Cesario crashed on the top of the mountain.
Now if the numbers for homologation and evolution were greater than 5000 and 500 respectively, a certain Nissan Skyline GT-R didn't come along (admittedly a magic car, the definitive Group A weapon) and the homologation process sorted out (possibly a modern day "parity" formula?) maybe Group A would have survived longer. Certainly the cars were more technically interesting than the V8Supercars we now have in Australia.
I've almost finished reading the excellent
Bernie's Game (if ever there was an author across his topic, its Terry Lovell) and I was surprised that the WTCC was never mentioned. I can see why Bernie was worried that the WTCC could be a threat to F1. The manufacturers like Ford, BMW and Alfa Romeo were tipping a lot more money into this series than F1 at the time and as FIA deemed F1 to be the only "real" international series I could see why Ecclestone would want to replace it with a series he could control like the doomed Silohuette formula for 1988. And to think that the European Touring Car C'ship was scrapped after 1988 - it was the beginning of the end of Group A and touring cars has never been a world-unifying force since, which suits Bernie just fine.
Ray, I can understand that Bartlett and Riley would be a little hazy about the whole Maserati affair, and now why Bruno Giacomelli (who didn't qualify at Bathurst

) didn't return your call.