[TR] FW: Head studs Q

Randall TR3driver at ca.rr.com
Fri Jul 29 03:45:58 MDT 2011


Carl wrote:

> According to the S/T Parts - pg 1.
> stud lengths changed at 13052E although it looks like the 
> head changed at
> 9350E.

The head change at 9350E was to the "Le Mans" head, which was still a low
port head (and therefore took the same studs, manifolds & gaskets as the
earlier head).  The change from low port to high port head was at 13052E.

> from:
> 6 x 106959 = 5"
> 4 x 106960 = 9"
> 2 x 113570 = 5 3/8"
> 1 x 121734 = 5 9/16"

Each engine only needs 10 head studs, not 13!  I believe the first two lines
are the correct listing for early engines with low port heads.  Then at the
introduction of the high port head, all of the studs on the RH side (where
the ports are) got longer.  So for early high port engines, the transition
was:

(6) 5" -> (3) 5" + (3) 5-3/8
(4) 9" -> (2) 9" + (2) 9-1/2

Then at a later, unspecified point (and this is where the mistake comes in),
the rearmost stud on the RH side got longer by 3/16" to accommodate the
engine lifting strap.  So the last two head stud lines in the SPC (for (2)
113570 + (1) 121734) are supposed to be in place of the (3) 113570 listed
after TS13052E.

-- Randall  


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