References for information on these pages

Ignition dwell angle for Mk1 & GT6+:
Triumph Service & Repair Handbook, TR2-TR6 & GT6, 1954-1971, Clymer publications, fourth printing (1972), page 32

Ignition condenser capacitance:
Triumph Service & Repair Handbook, TR2-TR6 & GT6, 1954-1971, Clymer publications, fourth printing (1972), page 32

GT6+ idle speed:
Triumph Service & Repair Handbook, TR2-TR6 & GT6, 1954-1971, Clymer publications, fourth printing (1972), page 32

GT6 Mk1 idle speed:
Triumph Service & Repair Handbook, TR2-TR6 & GT6, 1954-1971, Clymer publications, fourth printing (1972), page 32

GT6 Mk1 recommended fuel:
GT6 Driver's Handbook, British Leyland Motor Corporation, page 7

GT6+ recommended fuel:
Triumph GT6+ Driver's Handbook, British Leyland Motor Corporation, page 8

GT6 Mk3 recommended fuel:
Triumph GT6 Mk III Driver's Handbook, British Leyland Motor Corporation, page 21