Just a friendly note in the spirit of "bench racing" to clear up some
misinterpretations of my post....and perhaps I misunderstood the post I was
responding to...and perhaps we're comparing apples and oranges with 4 and 6
cylinder TR engines...but anyway...
>That's the salient point: were they cast-iron guides?
Yes they were, but no, that's NOT the salient point. The salient point is
that anywhere there is moving, stressed, metal to metal contact, adequate
lubrication is necessary. Whatever kinds of metal are involved.
>...Volume of the stock pump is adequate for SCCA.
At no point did I suggest that the stock oiling system was inadequate,
merely that it was not OVER lubricating the top end to the point where a
seal was necessary. Those of you who have added external oil feed lines may
have different experiences.
My feeling that the seals contributed to the early demise of the guides was
not the fact that they were worn, it was the fact that they were MORE worn
than the exhaust valve guides which had no seals...
>Consider that almost every engine today with an aluminum head
>(and aluminum heads are almost universal today) is equipped with hard
>valve inserts and aluminum-phosphor bronze valve guides...
>Why then are similar materials so inappropriate for the Triumph engine?
I never, ever suggested this, and, in fact, If you read my write-up of my
top end rebuild, you'll find that I used hardened exhaust seats, stainless
steel valves, and aluminum-phosphor bronze valve guides.
>It might be heresy to say so, but the engines in most of our cars never
had the benefit of newer technology, and the general belief, because of
that, is that the designers did the best with what was available.
Which is exactly why I used the above materials. And a copper head gasket,
and a silicone valve cover gasket. And a pertronix ignitor, grosse jets,
etc...and when that cool aluminum head becomes available from Moss Europe, I
may try that out too...
I remain convinced that a seal designed to keep lubrication out of an area
where it is needed is a bad idea. Unless your goal is to build a absolutely
smoke free engine at the expense of critical lubrication, valve stem seals
in a 4 cyl TR are a Band-Aid cover up of another problem. Either too much
oil up top, or too much clearance in stems/guides. I have no experiences
with TR6's so none of the above may apply to them...
Respectfully submitted, YMMV :>)
Chris Lillja
'66 TR4A
'74 Norton Commando 850
'71 Spit MKIV
http://members.aol.com/lilljaweb/index.html
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