This is taking the old brain back to where the fog starts getting really thick but I do recall something about 454's and valve train troubles, especially early 454's. I recall that a very small hole was drilled in the front oil galley plug (or plugs) that bled the trapped air out of the galley and also squirted oil on the back of the cam gear and timing chain. One of the other guys may recall more detail on this.


Evan