I picked up this 88 4runner about a month ago and have been trying to get it up to speed. I have this knocking sound at about 2000 rpm. It is most apparent at slight throttle and when initially getting on or off the pedal. It does get louder as it warms up.

I have 170-175psi across all four cylinders. The timing chain guide is intact(I thought it was this initially) and I have adjusted the valves.

I am assuming the worst that its a rod knock but would like some other opinions before I take off the oil pan. Here is a short vid.
http://m.youtube.com/watch?v=8V3LHQWc6Ww