Christopher Tidy wrote:
William Noble wrote:
"Christopher Tidy" wrote in message
...

Hi folks,

This question came into my head a few days ago. I often hear people
suggesting that the latest vehicle engines last longer and are more
trouble-free than older engines. But I also hear people saying, just
as often, "They don't make them like they used to".




short answer, "yes", at least for automotive use. I have 1936, 1938,
1951, 1959, 1985, 1986, 1993, 1997, and 2001 vehicles under my
purview. up through the 51 year car, 150K miles or so was the limit
- at that point the bores were 40 to 60 over, rings shot, no
compression, crank oval, no oil pressure, etc. 59 is good for 200K
easy. there was a major change in the metalurgy of the engine block,
etc, as I understand it - we can debate what changed, but the
longevity is just not an issue.

Thanks for sharing your experience, William. If any designers out
there know of significant changes in car engine block metallurgy over
the last 50 years or so, and are able to share them, I would be very
interested to hear.

I'm under the impression that cast iron blocks and/or cast iron
cylinder liners were the norm in the 1950s, and that cast iron liners
still are today, but I could be wrong. There have been some engines
which use coated aluminium cylinders, but after the Nikasil and
sulphur problems in the 1990s, I thought they were in decline.

Best wishes,

Chris

Chris,

I am not sure of the specifics but there is cast iron and cast iron, it
varies dramatically depending on composition, application and how the
part is produced. IIRC Ford used a higher chrome CI in casting some 302
block for high spec applications in the 60s to reduce wear. I am not
sure but would expect iron liners could be produced with far better wear
characteristics than a CI parent metal bore but also at high price. Not
neccessarily applicable to CI but a mate that works for Ricardo has
mentioned on a number of occasions that specialist foundries do the
likes of aluminium heads as control of dendrite size and orientation is
critical to the success of the head. IIRC the dendrite formation is
controlled so the highest strength characteristics are at the head to
block face.