How to read a Brisk spark plug reference
Brisk's Identification System encodes the shell (thread, reach, hex, seat), resistor, heat range, spark-gap design, electrode material and gap. Here is how to decode it.
A Brisk code such as DOR15YC-1 reads position by position: shell letter, optional O (special projection), R/X (resistor), heat range, spark-gap design, electrode material, then the gap suffix.
1. First letter — shell (thread, reach, hex & seat)
| Letter | Thread | Reach | Hex | Seat |
|---|---|---|---|---|
| A | M10×1.0 | 19 mm | 16 | gasket |
| B | M12×1.25 | 19 mm | 16 | gasket |
| D | M14×1.25 | 19 mm | 16 | gasket |
| F | M18×1.5 | 11.2 mm | 21 | taper |
| G | M14×1.25 | 17.5 mm | 16 | taper |
| L | M14×1.25 | 19 mm | 21 | gasket |
| N | M14×1.25 | 12.7 mm | 21 | gasket |
| R | M14×1.25 | 25 mm | 16 | taper |
(Other shells: C, E, H, J, K, M, NA, P, Q, S, T, U, X, 3V — same idea, each fixes a thread/reach/hex/seat combination.)
2. O — projection
An O after the shell letter marks a special metal-shell projection into the combustion chamber (still ISO-compliant).
3. R / X — interference suppression
- R — built-in interference-suppression resistor
- X — resistor reducing electrode burn-off
- none — no suppression
4. The number — heat range
The two digits are the heat range: 19 = hottest … 08 = coldest (higher = hotter). It is relative to Brisk.
5. Spark-gap design
- Y projected insulator nose · L extremely projected
- D two electrodes · T three electrodes · G ring-shaped electrode
- Z two auxiliary electrodes + ring gap · M special design · none = not projected
6. Electrode material
- none — nickel alloy · C copper core · E copper core + yttrium
- S silver · P platinum · IR iridium
7. Spark gap (suffix)
-1 = 1.0–1.1 mm, -3 = 1.3 mm, -5 = 1.5 mm, -9 = 0.9 mm, none = 0.4–0.8 mm, -T = special.
8. Tightening torque
Torque depends on the seat, thread diameter and cylinder-head material. Flat seat (with gasket): 10 mm 10–15 N·m (iron) / 10–12 (alu), 12 mm 15–25 / 15–20, 14 mm 25–35 / 25–30, 18 mm 35–45 / 35–40. Taper seat: 12–14 mm 10–20 N·m, 18 mm 20–30. Always follow the value printed on the box.