Differences Between MK I and MK II
It is said that the MK I bodywork is made from thicker and better quality steel and is therefore less prone to rust but given that even the youngest Stag is more than 40 years old rust is still a major factor for consideration when buying. Click on Buyers Guide to be taken to the section that highlights the vulnerable areas and what to look out for.
There’s no particular advantage or price premium to be paid for buying a later MK II Stag – it’s all about the cars condition and originality.
During its seven year production run the Triumph Stag outwardly changed relatively little and inevitably during the intervening period many MKI’s have acquired the persona of a MK II.
Production Changes by Commission Number
LE Federal (US Stags)
LD UK Stags
1 to 3900 1970 Pre-production and 1971 MK I cars
10001 to 14158 1972 Model Year and MK I
20001 to 25432 1973 Model Year MK II cars Black tail panel and sills
30001 to 36714 1974 / 75 Model Year MK II cars
40001 to 45722 1976 / 77 Model Year MK II cars Body colour tail panel. Alloy sill covers
Visual Differences
To assist the following table and photos document the majority of visual differences.
MK I Badges in Grey
MK I Steel wheels with Rostyle hubcaps
MK II Badges in Black
MK II Alloy wheels. Valve in front of spoke helps to denote original fitment – after market wheels often have the valve between spokes.
MKI No coach line or thin chrome sill strip
Chrome strip introduced for early MKII at LD 20001
MK II Twin coach lines. Initially the sill and back panel were painted matt black. In model year 1976 / 77 the thin chrome strip was replaced with stainless steel guard covering the whole sill and the matt black paint discontinued.
MK I Hood has three windows
MK II Hood has single large window
MK I Triumph bumper plinth bigger and contains the rear number plate lights.
MK II has a smaller Triumph name plinth as the number plate lights are in the boot lid.
MK I Instruments
Speedo & Rev Counter
Warning Lamp Cluster
Needles on dials hang down
Map Reading Light in Glove Box Lid
Interior Lights on B Pillars
MK II Instruments
Speedo & Rev Counter Updated
Warning Lamp Cluster Updated
Needles on dials point up
No Map Reading Light
Single Interior Light on T Bar
MK I No Headrests
MK II Headrests Provided
MK I Engine
Lower compression ratio with flat topped pistons and combustion chambers.
Air cleaner with twin inlet although a few late MKI (and just about all cars bound for the USA) had the later single air inlet.
MK II Engine
higher compression ratio with redesigned domed pistons and combustion chambers.
Air cleaner with single inlet with temperature control.
Acknowledgements:
Information verified by Stag Owners Club historian and archivist Peter Robinson and by making reference to “Original Triumph Stag” by James Taylor ISBN 1-901432-24-6 and “Triumph Stag Resource” by Andy Simons.
Article written by Roger Gray