after changing the bottom end twice and going through 3 different heads on my 2wd cossie i have come to the conclusion that the tapping in my engine must be the timing out.

i put bottom pulley to lug next to groove
top pulleys to each other
aux pully to the half moon .

would the pistons tap the valves if it was onlt very slightly out??
it turns over easy by hand but taps when running.
thanx