Triumph TR3A

vs

Triumph TR7

UK vs UK — 1957 vs 1975

Triumph TR3A (1957)
Triumph TR7 (1975)
Specifications
TR3ATR7 Drophead
Horsepower100 hp92 hp
Torque122 lb-ft112 lb-ft
Engine Size1,991 cc1,998 cc
0-60 mph10.8 sec9.1 sec
Top Speed105 mph109 mph
¼ Mile17.7 sec17.0 sec
Weight2,100 lbs2,238 lbs
Wheelbase2,235 mm2,159 mm
Length3,835 mm4,064 mm
Units Produced58,236112,368
Original MSRP$2,625$7,000
Value (Excellent)$65,000$25,000
Collectibility7/104/10
Rarity4/103/10
The Verdict

It's a closely fought contest. The 1957 Triumph TR3A brings lighter weight, stronger collectibility to the table, and the 1975 Triumph TR7 Drophead answers with quicker acceleration, higher top speed, better value. Both are excellent machines that reward their owners in different ways — there's no wrong answer here.

Overview

Triumph has long offered a diverse lineup, and comparing the 1957 Triumph TR3A with the 1975 Triumph TR7 Drophead highlights the breadth of the marque's engineering philosophy. On paper, the two are remarkably close in power output, with the 1957 Triumph TR3A producing 100 hp and the 1975 Triumph TR7 Drophead delivering 92 hp. Under the hood, the contrast is notable: the Triumph TR3A uses a Inline-4 OHV 8V displacing 1,991 cc, while the Triumph TR7 relies on a Inline-4 OHC with 1,998 cc. In the sprint to 60 mph, the 1975 Triumph TR7 Drophead edges ahead at 9.1 seconds versus 10.8 seconds. On the collector market, the 1957 Triumph TR3A commands a significant premium over the 1975 Triumph TR7 Drophead, reflecting differences in prestige and rarity. From a collectibility standpoint, the 1957 Triumph TR3A rates higher among enthusiasts and auction houses.