Pinking, pinging, timing adjustment

hello, My 1990 tercel (manual, carburetor E3 engine) that has a metallic rattling noise when the car is warm, and I accelerate briskly or maintain freeway speeds on a slight grade. I have replaced the cap/rotor/wires/spark plugs/timing belt(dealer). the noise still persists. I have looked over the engine and I don't think it's a loose part. I consulted the 'net and I assume the noise is caused by "pre-ignition." So my question is how do I adjust the distributor so the ignition is slightly retarded? or should I just pay someone to do it? Thank you!

yeah your timing is advanced too much... i have a 90 tercel with the 3E in it as well and i experience the same problem. if you don't want to deal with it, just run plus or premium fuel... it will go away. if not, there's two bolts that hold the distributor to the head, you're gonna need a timing light hooked to cylinder #1 and bring the timing mark back to about 3-5deg BTDC.. anything more and it'll ping like shit... if you can't do it... pay someone to do it.

thank you!