Which production car held the quarter mile record in Australia in 1971?

The VH Charger...

"we achieved a time of 14.8 seconds for the quarter mile -- on smoother surfaces the Charger galloped away so easily that a best of 14.5 seconds is with in reach".

The Chrysler Valiant range was released in Australia in June 1971.

http://www.chargerclubofwa.asn.au/production-detail.asp?iProductionID=31

The Phase 3 was the world's fastest four door production car for many years and in 1971 it won the Bathurst motor race in the hands of Alan Moffat, however the Chrysler Valiant E49 Charger held the 1/4 mile record in Australia.

The Phase III GTHO was the worlds fastest production car in 1971 but the 2 door Charger E49 Coupe held the 1/4 mile record for a production car.

https://en.wikipedia.org/wiki/Ford_Falcon_GTHO_Phase_III

265 E49 Six Pack 302@5,600 320 @ 4,100 10.0:1 14.4 quater mile seconds 6.1 sec 0-60mph.

The VH E49 Charger had a higher performance 265, and it set a record for being the fastest mass-produced car acceleration of any Australian production car - 14.4 seconds in the quarter mile.

http://www.valiant.org/ausval.html