i'm at 42k, think i should do plugs and stuff too?

ran a 15.1 at 90.
my last was a 15.2 @ 93.6

my only new mod is that 75mm maf. so either the maf is killin me, or the pinging is. i hope its the pinging.
i'll be buyin octane booster next time i roll up to the track.

-jason