'84 22re engine noise

[gasass]

Recently rebiult a 22re. Runs great except I have rattle that has me baffled. Before I tear it down I thaught I'd get some input. It Makes a ping or slight knock sound when I shift and when I just rest my foot on the accelerateor. Never under a load or on acceleration. I have an aftermarket cam which is slightly better than stock. Checked the valves three times, tried adjusting the timing, adding octane booster, you name it. scince I didn't have the funds to replace the injectors yet could it be an ignition knock? any comments would be appreciated.

[thousand_five]

rings maybe shot.... lifters?
Mine knocks too. as long as my mpg stays around 40 I'm cool w/it.

[Doctor J]

Could be exhaust manifold shield, loose exhaust pipe to transmission bracket.