Does anyone know the spec for the main bearing bores? Mine are 0.001"-0.002" wider than tall. This is a z6.
This is what they teach us in mechanics school as a good generic value to use. Mostly for larger pins than what a D16/D15 has, but its still a good number to use as a "ok this needs to get fixed" threshold.Here is the first good data I've found on this subject. He says that if the block is out of round it can be up to .001" at the parting line. (not vertically)
Geometrical parameters of engine bearings [SubsTech]
We used to reckon with cast iron engines that both parts were distorted slightly, so if the block and head materials are similar, you may have a point.I thought you needed a head plate or an actual head torqued down on an inline engine in order to properly line bore it?
doesnt the head squeeze the block out of shape slightly?
Not a bad setup at all as Kaiser makes some really nice boring heads.I drew up I circle (2.3228") and an elliptical "circle" in cad that is .001" wider than the circle. You would have to cut off .026" from the cap and the block to bring the parting line back into the circumference of the round circle. So align boring isn't going correct this. Chopping 2 thou off a cap and honing will do nothing if the bore is too wide.
Here is a video of the best attempt I've seen at a proper line bore. Notice the blue across the parting line when they are done. The machine didn't even touch the sides. I wonder if the bearings are just flapping in the breeze or if they actually bend and touch.