yes, lean AND knock. Isn't that usually the case? Mixture lean == more volatile == premature combustion.
Anyway, I found what the problem was: My MAF sensor was dirty. There was a LOT of goob on it! Partly already there when I bought the car in 2001 (with the knock), partly made worse by installing a K&R airfilter.
I cleaned it with Windex and a Qtip, put it back, and bam, my 0-60 went from 11 seconds to 8.8 seconds! That's what I call a good mod! And the best thing, the spark knock is (almost) completely gone, it's only present when I have 4 persons in the car, going uphill, in 100F Austin, Texas. Finally I can get $1.17 regular instead of $1.35 premium again!.
I'm happy! My car runs as it should. I think. Power seems to really kick in at 3500rpm, and the car is pretty sluggish before that. Could be the stall speed, but surely that's not 3500rpm... Is 8.8 secs on a 0-60 normal for a '97 4.6l?
Anyway, on to the mods. I think a Dennis Reinhardt chip is the first thing...