I did a full PI head swap including BBK headers and still get a small tick/ tap from the passenger side. I am running the 2V Romeo setup. Nothing is wrong with the block and there is also all a brand new timing kit that was done. I know that on the 302 (5.0) setup you get quite a bit of upper valve tick of which you can mainly hear under the hood but not much outside when the hood is closed. On my Expy I find more noise through the fender well and not much under the hood. I was able to trace back my noise to echoing through the headers and carried into the stock cats on the passenger side. One other thing is typically you will find a bit more noise echoing with headers.