spark plug

[Loren]

The OE plugs are really GREAT plugs, and under "normal" driving they should last 100k miles. (so they say... at least 50k)

But, my experience with them after a fair amount of track use (lots of time at or near the redline, almost constant full-throttle acceleration for 20-40 minutes at a time) was that one of them started giving high-rpm misfires at about 18,000 miles.

If you're just using the car for commuting and general driving, don't waste your time and money on spark plugs until/unless the computer throws a CEL for misfires. You're just throwing money away. And then, if you get 50k or more out of the OE plugs, the were obviously a good choice... replace with the same!

If you do any sort of competition on a regular basis, you're better off switching to a standard (not iridium, not platinum, not unobtanium) NGK plug and just changing them every 10-20k. There is SO little performance to be gained by using uber-expensive plugs, it's just not worth it.