DENSO model compilation: (1)? （2）? （3）? (4)
1. Common thread diameter: m? 18mm, hexagonal opposite 25.4mm
W? 14mm, hexagon opposite 2.6mm
X? 12mm, hexagon opposite 18mm
U? 1mm, hexagon opposite 16mm
2, calorific value: heat <; > Cold
4, 9, 14, 16, 17, 2, 22, 24, 25, 27, 29, 31, 34 and 37
3. Thread length: E? 19mm
F? 12mm
L? 11.2mm
marking? 12mm（? 18mm）/9.5mm（? 14mm)
4. spark plug type: p? Insulator protruding type
L? Short seat type
S? Ordinary type
R? Damping resistance type
N? Racing type
M? Small
U? U-shaped groove electrode type
DENSO iridium spark plug, which is used to be called Denso iridium spark plug. It is the main product of Denso in Japan. The diameter of ignition electrode of .4 is the thinnest in the world, which requires low ignition voltage, fuel saving and quick explosive force. It is the designated special spark plug for F1 racing car and a supporting product of Toyota. Denso's patented U-groove technology is the only one in the world, which increases the ignition explosive force and makes the combustion more complete.
(photo/text/photo: Shi Lili) @219