When I was driving back to work from lunch today, I was "designing in
my head" a test fixture for testing head gaskets. Basically, take a
block and attach a piston in one of the cylinders such that it doesn't
leak and doesn't move. Install the head and gasket (ideally, brint it
up to operating temperature by running heated water through it) and
increase the pressure in steps until the the pressure decreases
showing that the gasket blew.
It's a test fixture that would be simple to set up, and if I had any
free time whatsoever, I'd love to do just to learn what makes gaskets
work. Of course, it doesn't accurately reflect the "hammering" effect,
or shock of detonation, but it's probably indicative of what does and
doesn't work for non-shock pressure loading.
This made me hypothesize on why cars are more likely to predetonate
going uphill rather than on the flat. In addition to the back force
from inertia and drag, there is also the added force from lifting the
car up the hill. With more force on the piston (and no predetonation)
divided by the same area, there is more pressure in the
cylinder. Likewise, a lighter flywheel could slightly reduce pinging,
less rotating inertia, less force on the pistons, less cylinder
pressure.
Am I at all close here?
--
I've found something worse than oldies station that play the music I used to
listen to. Oldies stations that play the "new" music I used to complain about.
lrc@red4est.com http://www.red4est.com/lrc
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