Anyone have the tolerance for "out of round" and "taper" for the 4.6?
My manual is unclear at best.
Page 303-00-33 out of round = .0007
page 303-00-67 shows = .0006/.00079

page 303-00-67 shows taper = .00023

Is this correct?

 

The tolerances are very tight.
The out of round of .00007 is in the middle of the range of 6 to 79 so nothing is really incorrect as a tolerance.
The taper is even very tight to keep ring seal on the piston lands and reduce wear at those points.
You need good cylinder tools to read the values of .000xx accurately.
The penalty for being too tight is hard cold starting and scuffing.
To loose is cold start noises until the parts heat and expand.
The block and pistons change in dimension nearly that much from cold to hot so has been engineered for the best expansion in materials and clearances.
When using after market pistons and parts you really don't know what the expansion rates are and just trust it is near the same.
Not like the old days.
Good luck.

 

Agreed, here's a interesting thing. I'm showing NO ridge ring at all, none and I can still see the cross hatching. The cams, crank, cylinder walls, even the heads coolant passages look perfect. Taking the crank to a shop today to have them look at it but I measured it and it shows still in tolerance so maybe all I need with it is polishing.....we'll see.
All of the rings look perfect as well....I don't get it, I thought I would have seen some wear but I see none. The whole reason I pulled it now was that I was getting a CLICKING noise that went away after it warmed up but I did not trust it, so I pulled it. Now I'm thinking I could have left it and kept on driving.
The bottom line is I DON'T SEE ANY WEAR.