[TR] TR4 Spin On Oil Filter

[Randall]

> In theory, this seemed to my (admittedly untutored) judgment, 
> that fewer particles would make it through the filter to 
> abrade metal surfaces.B

Well, I can't claim to be an authority either, but the picture seems much
more complicated than that to me.  From what I've read, particles that are
small enough cause much less wear than larger particles, so there's really
no point in worrying about them.  And the kicker is that bypass valve that
opens when the filter media becomes clogged ... seems likely that smaller
holes would make it easier to clog.  In fact, at some point, the small holes
will restrict flow so much that the bypass will open even with a clean
filter.  And even below that point, it's still restricting flow into the
engine.

So as with so many other things in engineering, there are many tradeoffs to
be made and not necessarily a consensus on the 'right' value for each
tradeoff.

> Since I know he also uses high quality 
> Valvoline multi-viscosityB

Yes, I do.  Had some bad experiences with other oils.

> maybe filters don't mean 
> as much as quality oil.B 

Could be.  Up until the 50s, many auto makers were claiming that oil filters
did not add significantly to engine life (which may have been more of a
statement about the filters available then).  The oil filter was optional on
my first Chevy.  And early TRs used a wool felt filter configured as a
bypass ... filtered oil was dumped back into the crankcase and the galleries
got oil directly from the pump.

There was an interesting modification being sold back in the 70s; that
bragged you never needed to change oil again.  It used toilet paper as the
filter element in a bypass type filter.  Friend of mine had one on his
Buick; and it did seem to perform as advertised.  His oil stayed visibly
clean and golden for several years; and his 455 engine showed no signs of
distress.  But eventually he got tired of having to change the TP every 1000
miles (and add a quart of oil), so he went back to the stock filter.

Randall