Without seeing things it does sound possible the timing belt may be the issue. The timing cover would have to be removed to see whether it is moving when cranking.
Did you machine or replace the brake rotors? If not, did you chamfer the edges of the pads before installing? If the rotor has a ridge on the outer and inner pad contact area the pad contact will not be ideal. I have replaced pads many times and only chamfered the edges with no problems.
If you have a grinder you take off the outer and inner corners of the lining slightly. Don't have a grinder? Use a file and rub the brake pad across the file teeth. The corners of the new pad will tend to contact the ridge of the rotor and the center area will not make full contact to the rotor. If rotors have been replaced or machined chamfering is not so critical though I do it slightly anyway.
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Shameless bump, just in case there's anyone that didn't know what a great guy 73 was, read this thread.