Cross-Reference
NGK BPMR7A vs BPMR8Y: Heat Range and Electrode Differences
Updated 2026-10-16
NGK BPMR7A and BPMR8Y share a 14 mm thread and 9.5 mm reach. BPMR8Y is one step colder with a V-grooved projected electrode. See which equipment uses each.
What is the difference between BPMR7A and BPMR8Y?
Two things. Heat range: NGK numbers run hotter to colder as they rise, so BPMR8Y is one step colder than BPMR7A. Electrode: NGK's Y suffix means a V-grooved centre electrode with extra projection. Thread, 9.5 mm reach, resistor, and projected insulator are shared. Echo's PB-500 record lists BPMR8Y; Stihl and Husqvarna records list BPMR7A.
Read the manufacturer referencesDirect Comparison
| Check | NGK BPMR7A | NGK BPMR8Y | What decides fitment |
|---|---|---|---|
| Heat range | 7: one step hotter | 8: one step colder | NGK's higher number is colder, the opposite of Champion. Use the plug your manual names. |
| Centre electrode | Standard design | Y: V-grooved, extra projection | A design difference, not a fitment difference. |
| Thread and reach | 14 mm thread, 9.5 mm reach | 14 mm thread, 9.5 mm reach | Same shell. |
| Resistor and insulator | R resistor, P projected insulator | R resistor, P projected insulator | No difference. |
| NGK stock number | 4626 | 2218 | Use the stock number to confirm the listing is the plug you meant to buy. |
Compare the Parts
Match the plug specified for your equipment before choosing a listing. Check the part number again on Amazon before ordering.
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Do Not Read NGK and Champion Numbers the Same Way
NGK's catalog key runs heat range from 2 (hotter) to 11 (colder). Champion runs the other way: its higher numbers are hotter. A 7 from NGK and a 7 from Champion are not the same heat range.
That is why cross-references come from the catalog, not from matching digits.
Which Equipment Uses Each
In our records the Echo PB-500 backpack blower lists NGK BPMR8Y at 0.6 mm. The Stihl MS and FS models and the Husqvarna 128LD, 130, 135, and 435 to 460 list BPMR7A.
Swapping one for the other changes the heat range by one step. Use the plug your model page and manual name, and set the gap to that model specification.
Primary Sources
- NGK spark plug catalog and code keyDefines the heat-range direction, the BPM reach, and the P, R, and Y codes, and lists stock numbers 4626 and 2218.
- NGK BPMR7A application specificationProvides BPMR7A thread diameter, reach, and wrench size.