interesting. before I tore into my 505 to check bearings (for the hell of it), I was checking vacuum the last time I drove it. It had more than I was expecting , 8-10- at idle, as hi as 16 at other times. this is w/ a .628 solid roller, 254-260 @ .050.----- the inside of the engine looks great, but after pulling the plugs, I noticed # 7 was colored like a paper sack, the rest were soot black, -------- comments ???
