Egg Shaped Piston Journals

To check the crank I would suggest you get yourself a micrometer and start measuring. Each throw should be measured twice at 90º for one another. I measure them at 4 locations, a measurement at each side and then again at 90º to also check for a taper.

Let us know what you come up with.

Have you done any of the previous suggestions ?
 
As a general rule, the most wear occurs about 10-20 degrees after top dead center, where combustion pressure is the highest. To be safe, mike in several places around the journal, first near the front of the journal and then near the back, to check for both taper and out-of-round. If you are going to use Plasti-gage, a note of caution: After torqueing the rod and you go to remove the cap, they often stick. The normal reaction is to get a hammer and tap on the rod bolts to loosen the cap. Don't do it! This will flatten the Plasti-gage strip even more and give a false reading. You may flatten the strip down to read .001" and you think it's good, but it may be 5-10 times that! Years ago my brother-in-law put a crank kit in a six cyl. Chevy and had this happen. Turns out they gave him std. bearings and .010" under crank. Of course it knocked! He said it was good when he Plasti-gaged it. I asked him the procedure he used and he told me he had to tap on the rod caps. This explained it.
If you don't have a mike and the rods and crank are out of the engine try trial fitting the rods to the crank. Install a rod with one or two less shims than was in it and tighten the cap. If it still turns free, repeat until there is noticeable drag and reinstall a shim or two to get just a very slight drag. If the crank is egg-shaped, you will find that the rod will be free in one spot and then have a drag. You could Plati-gage in that free spot and get a rough idea how egg-shaped the crank is.
In addition, you can use shim stock instead of Plasti-gage. Buy a cheap feeler gauge that goes down to .0015" and trim off about a 1/2" piece and deburr the edges. Lay it on the crank like Plasti-gage and torque the cap and check the drag. Go up in thickness until it binds. No danger of flattening a plastic strip but more time consuming. To check for .001" clearance, aluminum foil like Reynolds Wrap is about .001".
 
I checked #1 journal and it is .001 out of round. With conn at bottom of stroke, it is bigger. .001 smaller about 2 o clock position. I will set this one at .002 and see if it binds...At what clearance do you get "knocking"
 
out of round journals are not a good thing. If you plan on driving this car much you should have the crank ground.
 
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