Ignition lead set
Triumph: TR2, TR3, TR3A, TR3B, TR4 and TR4A (1953-67)
for Lucas DM2P4 and 25D4 distributor with side top cap
Almost all spark plug wire sets sold today are a radio noise suppression type that use a carbon core as the conductor instead of copper wire. The carbon core tends to crack and loose some of its conductivity over time from engine vibrations and each time you remove a spark plug or change a distributor cap. This gradually reduces the spark available at the plugs, which is seen as a gradual loss in power and fuel mileage.
For top engine performance and fuel economy we recommend that the plug wires be replaced every time the plugs are. Caps and rotors arms should be changed as a set. If you do not have electronic ignition installed, the contact set gap should be checked frequently (Limora recommends every 3.000 miles). Slipped contact sets are often mistaken for carburettion problems. Before the carburettor, check the gap.
