Gascoop

Speaking of valve covers, does anyone know of an adapter being made for 394's onto a 455 or is it even possible size wise? Love the look of the older VC's

OLDSter Ralph

Nothing is impossible.
I am wondering about the height of the valve train above the gasket surface. I am thinking the 455 rockers are higher than the 394. Maybe someone with a 394 can measure the height, width and length. Next you would have to compare the bolt hole sizes and locations.
You might want to consider a set of chromed 73-74 valve covers with Oldsmobile stamped on/in them.

Gascoop

NAHHHH, too ordinary, if no one makes them then oh well, was just an idea. Here's a set of adapters I used on the 507" Cadillac I built for my '32 Ford. The guy only made a few sets and it allowed ..... I think they were PMW Corvette looking finned valve covers, course they had Cadillac on them. Everything fit nicely.

Tedd Thompson

I know of a guy who took a 394 and adapted early valve covers on it. Quite a process as he had to make hangers for the center valve covers to bolt up to. Looked cool as hell with 303 style covers and it went like stink back in the stop light to stop days.... Tedd