Bob Kramer wrote:
> I have lost my saved emails in a computer snafu. Did
> aanyone save the emails (and address book) about
> reinforcing the combustion chambers in the TR4 head
> with a threaded pin,and could you forward them to me?
Bob -
I've copied the three that I saved below, in the order they were sent.
Jim Hill
Madison WI
=====================================
----- Original Message -----
From: "Tony Drews" <tony@tonydrews.com>
To: <fot@autox.team.net>
Sent: Saturday, February 16, 2002 4:41 PM
Subject: RE: Cylinder head thickness / reinforcement
> I have a head that used to belong to Jack Wheeler. It is milled
> 0.175". It is "pinned". The way Jack described it to me, to "pin" the
> head, you drill and tap a number of small holes around the circumference
of
> the combustion chamber directly over where the head would mate to the
> liner, opposite the combustion chamber. You use long, hardened set
screws,
> coat them with epoxy, thread them through until they hit the other side of
> the water jacket and then mill the head.
>
> In my head, you can see round shiny patches on the surface of the head
that
> are the "pins". I'll try to describe the locations of the pins: there are
> 2 or 3 of them inboard of the water jacket hole closest to the exhaust
> valve. There is one on the opposite side of the combustion chamber of
both
> of the valves. Total of 4 or 5 per combustion chamber. I've posted a
> description and a crude drawing of the pin locations on my website.
> Description and thumbnail picture is at the bottom of the following page:
> http://www.tonydrews.com/Tony_Car.htm
> The full size drawing is at: http://www.tonydrews.com/Tr-4_head_pins.jpg
>
> My knowledge of this is based on one head and the description that Jack
> verbally told me. If others have better descriptions, or alternate
> (better) locations for the pins, or other descriptions on what you do to
> glue the pins into the head, or other ways of reinforcing the head, I'm
> extremely interested them.
>
> - Tony Drews
=====================================
----- Original Message -----
From: "Greg Solow" <gregmogdoc@surfnetusa.com>
To: <fot@autox.team.net>
Sent: Sunday, February 17, 2002 12:56 PM
Subject: Re: Cylinder head thickness and the PHA
> What Jack [actually Tony] Drews posted looks about right. I would post a
photo but don't
> have a digital camera yet. The pins I have used are 10/24 machine screws
and
> the end of the screws sit against the outside bottom wall of the exhaust
> port. The first head I saw reinforced this was was off of Carl Swanson's
> Morgan. I bought the head from him in 1966. I think that the pining was
> actually done by Kas, or at least in the Comp dept shop. The weakest are
is
> that next to the triangular water hole at the rear of the head. I t is
> possible to look into the water jacket and see that the casting tapers
> gradually thicker as it goes farthur from the actual water paasage hole,
but
> is still quite thin and bridges a wide area with no internal support as
you
> follow the line of contact with the cylinder liner. The pressure of the
> cylinder liner, .003" to .006" proud of the block, and the heat and
> vibration stress while the engine is running tend to cause the head
surface
> in this area to warp up and away from the liner if this area gets to thin.
> The pins spread the load to the exhaust port bottom floor and prevent this
> "collapse."
> There are normall 3 pins in this area, about 3/8 " apart. These are
> dupicated in each of the cyinders. Then the is 1 pin in the "mirror image"
> location of liner contact, still on the manifold side of the head. The
head
> is plenty strong on the spark plug side. The only problem over there is
the
> "creep " of the spark plug cooling water passageway toward the combustion
> tchamber and head gasket sealing area as the head is milled more and more.
>
Regards,
>
> Greg Solow
=====================================
----- Original Message -----
From: "Kas Kastner" <kaskas@earthlink.net>
To: <fot@autox.team.net>
Sent: Sunday, February 17, 2002 5:43 PM
Subject: Re: Cylinder head thickness and the PHA
> Pinning the combustion chamber was one of the best things I ever did for
the
> Tr engine. I came up with that after a close inspection as has been
> described by others here and figured it out on the airplane ride home form
> Portland ( and another blown head gasket) . Fixed the deal and it's so
> simple. You do have to be careful if you skim or mill the head again
after
> installing the pins cause the hardened pins will eat up a mill end in a
> hurry. Surface grinding works fine though. Oh yeah, I did work out the
deal
> for Carl Swanson and several other people also. Can the mid 60's be that
> long ago??? Wow I must be older than dirt.
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