[twinharleys]

I have a 1993 evo motor making a loud tapping noise when engine is warmed up, no performance loss or smoke

[cdad]

Could be a valve tappet. And your just being lucky its staying alaigned. Have you checked that yet?

[twinharleys]

I checked lifters and push rods all seem normal

[cdad]

Is the sound coming from the top end? Have you been able to identify where its coming from? You can use a long screwdriver and hold the tip to various parts of the motor while its running and it should change how loud it gets when holding the other end to your ear. The other possibility is a wristpin is rattling around. Or your rod is coming loose. If its loud its serious.