Hi, recently had the dreaded chain failure, only slipped about 20 degrees so replaced both chain sets and fitted a z20 tensioner (all gm gear) I then ran the engine (started on the button) but unfortunately there was a slight misfire. So head off and found a slight bent exhaust valve and inlet valve so replaced all 4 valves on cylinder 2, new stem seals, No other damage found to head, no marks on pistons etc. Built it all back up, timing marks all lined up, fluid levels topped up all plugs checked and it just won't start, it made a slight chugging as if it would start so we opened the throttle body up by hand but the chugging just got louder, there is a strong smell of fuel but could it be fuel pressure? It has the continental pump. Any help appreciated as I'm stuck for ideas.