Crank Hole Finish Size For Pilot Bushing

Well, to clear up any confusion, this is a 66 273 motor with a forged crank! Every other motor and crank I have here is not only drilled and reamed, but all have the bushings already installed! They are 340's though, so I think that was automatically done with that displacement! The only other motor I have here is another 66 which is not reamed either! All have come from automatics!

Without further info, I am going to check the concentric of the unreamed hole with an indicator, and if it is concentric, I'm going to turn down the bushing and go that way! That will get me back on track the quickest and most economically!

Of course more input is welcomed, if anybody has anything to add please do!! Thanks, Geof