I was given a crank/engine from a 73 460 car (2yABC) that the previous owners says was turned. I assumed .10 over but after installing new crank bearings there was at least another .10 gap in there between the crank and rod bearing. The pistons from the same engine are .30 over so my next assumption is that the crank is .30 over. To be safe I was going to use a micrometer and measure the diameter of the crank and subtract that number from what the crank was brand new. So, two questions: What was the size of the crank from the factory and am I on the right track?

Thanks

 

When a crank is turned it is then undersized. You need to get your decimal points in the right place, but I /we know what you mean and yes, get a good set of mics that read in .0001" so you can determine how far it was turned before buying bearings.

 

Thanks for the reply. And thanks for not goofing on me for a stupid question. So when I order new bearings I would order then say .010 undersized?

 

No you should find out what the crank is and THEN order bearings.

stock specs in my book are crank journal 2.9994-3.0002 rod journals 2.4992-2.5000.

find out what yours are, then base what size bearings you need from that.

 

Crank is undersize, bearings are oversize.

 

My 2 cents are, make sure the mic is set right using a "standard"...they are many times out of wack and worthless...also check the journals in a few readings, rods too for roundness, theres not a lot to play with before reaching put out of service status