Originally Posted by james a larson
Maybe I am wrong. But if you remove .045 from the cylinder wall, you ae also removing .045 from the ajoining cylinder wall or a total of .090 from the distance between the bores.
So on a standard bore, if the distance between the cylinder bores is .750 and you have a gap of .375 between cylinders and you remove .045 from each, thats a total of .090 from the thickness of the 2 cylinder walls. So each cylinder wall would be .143 thick at the frost plug area.
I must be all goofed up as where where they are taking the measurment when they sonic test the cylinders. Can some explain where this measurment is taken?
the distance between the outside of the cylinder walls does not change.
you are removing a small amount of the inside of the cylinder wall during boring.
the way the cylinder walls are sonic checked (ultra-sound) is with electronic thickness measuring tool called an UT or ultra-sound tester.
several measurements are taken in a line up and down the cylinder bore from the inside.
the basic method is to test both sides along with the top side and bottom side of the cylinder wall (as you are looking down into the cylinder bore).
documentation of the measurements will map out the minimum/maximum thickness of each cylinder walls thickness in the areas measured.
this way if you need a minimum of 0.250" of cylinder wall thickness to safely run the engine, and the minimum cylinder wall thickness detected is shown to be say 0.310" then you could safely bore the block to remove a maximum of 0.060 total from the inside of the cylinder wall.
as the cylinder bore is measured as a diameter from one side to the other = if you took 0.050" from the bore it will actually be bored 0.100" larger...
i made an error in my previous post using radius when i meant diameter.
when you take 0.045" from the inside of the cylinder bore, this measurement is added to the radius, this increased radius measurement is 1/2 of the bore diameter= radius X2=diameter which then shows a total increase of 0.090" in bore diameter