it looks to be an 1981 model 616.
same 531 Reynolds frame, derailleurs, brakes, crank set (is Shimano 600EX same with Aarbesque?), seat post, saddle - except rear derailleur.
different rims - Rigida Alloy 27" (in catalog are Rigida Alloy 700).
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1992 Torelli Nitro Express; 1974 Raleigh Professional, Bridgestone XO-2