DENSO updates its spark plug heat range information
Cross referencing against products from other manufacturers is often a challenge, but particularly difficult when it comes to spark plugs. However, to help distributors and their workshop customers overcome the problems, DENSO has issued a helpful bulletin that addresses the heat range on M12 sized spark plugs, to ensure the correct replacement is easily identified.
In the bulletin, DENSO highlights the fact that it has updated the information concerning the heat range of M12 sized spark plugs in its identification tables, which clarify the technical aspects such as the sizes and measurements of its plugs.
The DENSO spark plug range is divided into original equipment (OE) and aftermarket (IAM) spark plugs and to identify the correct replacement from these two alternatives, requires two identification tables. Naturally, one is for the OE spark plugs and the other for the IAM upgrade technology plugs like the DENSO-TT, Iridium Power, Iridium Tough and Iridium Racing.
For some years, DENSO has used an alternative heat range for some M12 sized OE plugs with 9mm ceramic diameter, which might cause confusion. This size of spark plug uses a lower heat range number combined with a ‘C’ compared with the similar ‘XE’ type. However, although the C indicates one heat range lower than the XE number shows, the real size and heat range is same.
This is demonstrated in the table below, which shows that the DENSO Iridium TT IXEH20TT, is the appropriate upgrade alternative to the SC16HR11, FC16HR-Q8 and VFCH16 spark plugs.
The most important message therefore, is that C16 should be cross referenced with XE20, likewise C20 with XE22 and C22 with XE24.
For the correct cross reference information in TecDoc, please refer to what is mentioned in the technical specs as “Alternative item” in the DENSO information.