Knocking noise
 

Hello everyone,i m new member in forum,
I have 76 pontiac ventura and it has 76 8 head 350 olds engine,i have knocking noise that i already checked below items;
-flex plate conn with turbine,its ok
-hyd lifters ,its ok
-firing,its ok
Remain to check crank conn with pistons and timing chain,but when i check while engine run,increasing rpm noise not getting high when its idle rpm noise comes higher volume.My question is;could it be from lack or worn timing chain or other front engine parts.?
BRGDS