yellowrocket

Hi, looking for some info on books pertaining to blueprinting Oldsmobile engines . I have a '71 455 going to the builder and would like to find out if there is any deburring work that should be done prior to cleaning and machining.

TripDeuces

I usually just knock of any casting flash taking it back to the thick part of the metal. Don't have to get too crazy. You can knock the sharp corners off too with a stone.
One spot I never liked was the top of the bolt holes on the mains. They seem to always have a hole there so I hit that with a burr to get rid of the thin stuff then chase the threads with a bottoming tap if you have one. Don't get crazy with the tap. You don't want to remove metal just get the threads clean.
When it comes back from the machine shop no matter how clean it looks clean it again chasing every oil galley and hole.

joe_padavano

Deburring casting flash is just good practice to be done on any performance engine build. It's really common sense. Blueprinting involves measuring the actual dimensions of critical engine parts and machining them back to nominal if they are at the edges of the allowable production tolerances. All mass-produced machinery has manufacturing tolerances, as it would not be economically prudent to build every one to zero tolerances. This variation in clearances and dimensions is why one production line motor may run better or worse than another, and why (for example) the actual chamber volume of your particular set of cylinder heads may or may not match published numbers.