ngk br7ef is a stage colder than a tr6, tr7 and br7ef are same heat range but the tr7 are projected and the br7 isnt (it goes something like that lol)

i pulled up a stock tune file from a 98 gtp and my car was definately tuned cause they touched alot of different tables, has a bit more timing than stock, maf and ve tables are different

unless the 98's are different