Side to side liner height variance

[Rawze]

(03-08-2021 )Nilao Wrote:  When rawze cut mine I think it was .0135 on the intake and 14 on the exhaust....I forget the specs but I think the variance hole to hole was .002 but don't quote me on that...I'm sure rawze will be able to tell us to the nanometer later.

Yours ended up at 0.017 initially" -- so we re-cut them and ended up at 0.014" on the second go around with about 0.0145" on the passenger side (where it should be if there is variance).

Cummins says the tolerance allowance between holes is 0.002".
Cummins also says 0.001" from one side of a hole to the other.

I have never cut one hole-to-hole with more than 0.001" variance between holes, not even the very front to the very back, and any more than 0.0005" within the same hole on one myself. That is when I was using digital gauges, and have abandoned them since.


After I did Waterloo's truck with him, I threw away all my digital gauges into the trash can and went back to using only old-school mechanical ones. I can get the machining a whole heck of a lot more accurate with mechanical gauges than digital. Since then, If I see the 0.0005" variance in the cutting tool starting to set in, then I simply change the torque of the retaining bolts of the counter-boring tool a bit and can correct for it easily before getting to the bottom of the cut.

I would imagine that also, with the hardened brass shims, a bit of variance would be more forgiving vs. someone using hardened stainless shims. I am not a fan of hardened stainless shims at all... but that is just me.