1995 525i Manual, Black, silver interior, 164K miles. What spark plugs to use? The Bentley manual specifies spark plugs as Bosch F7 L DCR, but the Owner's Manual says Bosch F8 L DCR - which, according to Bosch's website, is one notch "hotter" than the F7. Meanwhile, I have seen plenty of old posts that say to use NGK BKR6EK. Why do I care? Just misses passing Calif. smog for HC at 15 mph on the dyno (passes at 25 mph). CO and NOX are fine. Already replaced fuel pump, filter and pressure regulator, as I am sure they were original (filter was really nasty inside the dirty side - yikes!). Still just barely over that HC limit at 15 mph, but starts and runs great. Plugs are not very old but figure new ones can't hurt, and have been told it's a good idea to replace the coil boots at the same time (I am sure they are original, so I agree). Anyway, what's up with spark plug choices? Gotta pass smog to drive the next 2 years!