I went from a 305 to a 383 thats all built and I have the long block in the car. Hope to be finished Wednesday. The problem is that I put Harlem & Sharp roller rockers on a pair of Dart heads and my stock centerbolt valve covers wont fit due to height and maybe the breathers. I want to get this engine done and running so I can take it to the track Sunday which is like a couple of days before it closes due to the weather here in Illinois. To temporarily fix the problem I orded taller pre 86 valve covers (non centerbolt) without baffels which will be in Wendnesday from Chevy. I want to have chrome centerbolt valve cover like I have now but I havnt ever seen any taller ones and I dont think ones with baffles and the breather things will fit. What do you guys think?

 

I'm running B&B cast aluminum valve covers on mine, big Comp Cams rockers that wouldn't clear the stock covers and they fit fine after minor grinding of the covers' interior supports.

http://www.stefs.com/bb/39.htm

For the non-polished set it was $130 or so, all the PCV holes and whatnot are in the same locations as stock.