I just looked it up on NGK's website.Went to Kragen/O'reilly today to try and get spark plugs. After 1/2 an hour, they gave me NGK Iridium BKR6EIX-11 and they said they were the same (or cross referenced) to the NGK PFR7G. They needed the stock number for the PFR7G's which apparently they could not figure out. Should I use them (NGK Iridium BKR6EIX-11)?
The BKR6EIX (Stock #: 2756) is the stock replacement.
The BKR7EIX (Stock #:6988) is the next heat range colder.
Most places, like the Bennett Auto Supply I just called, can't look up the plug by the above number. What they need is the "Stock Number." With the SN, they'll be able to tell you the part number. (Last time, I asked for NGK TR6's and they couldn't find them.)
The way NGK lists their heat ranges is as follows.
- The heat ranges go from 2 up to 12.
- The higher the number, the colder the plug.
Hope this helps,