Hi all.
And a glorious day it is!
Too bad I have two dead TR6's right now. On the plus side, with no TR6 to
drive, I am motivated to work on them. Spent over 5 hours on them today.
At any rate. Went to Mr. Machine shop today. I also went last friday and
last tuesday and a week ago last tuesday. Hell, if I was still married my
wife would be wondering why I keep going over to Revere...
But I digress.
Here's the story. I have a stock TR6 head from my 1974 TR6. The head is
original, and I have 110k documented miles on the car. I have put over 60
miles in the last 10 years, all of which have been with unleaded petrol, as
Massachusetts (and I believe all of the lower 48) banned leaded fuel
sometime in the '89 or '90 timeframe.
As a point of reference, I actually race this car, albeit autocross or
gymkhana, and the motor frequently sees 5000 RPM's. These are high stress
miles. Not nearly as highly stressed as the Yellow Bullet, I might add (Hi
Steve!), but stressed nonetheless.
Verdict. Valve guides were shot. No valve recession. The valve stems were
slightly galled on two or three intakes and the exhaust valves were about
the same (three or 4 were galled), but all were more or less okay
considering the number and type of miles on the car. As for the shot valve
guides, I will say that 110k miles is actually outside of the factory spec,
which I beleive would have had me do a real valve job at 48K miles (and
presumably 96k).
So, spend your money on your hardened seats, have the machinist take your
hard earned cash if you want, but I'm going to keep my original cast iron
head without any hardened seats, at least for now.
Note: the RaceCar (tm) will be running some serious compression, I expect
some problems with that head, but it'll make it through this year and
probably next before I go to town on it. That one will be seeing some
serious RPMs, if I ever get the money together for a set of carillos... and
the 10,000 RPM clutch etc. On the other hand, with that car I have the
option for some real good ol' "Panther Piss" 116 _leaded_ fuel. But at
$4.50 per gallon, I won't be likely to take that car for a leasurely 250
mile trip.
I'll let the list know what the 0 - 60 times are. I'm thinking in the lower
5.0's... anybody think I can do it?
Oh well.
Note: my machinist said, and I quote: "Those heads are pretty hard, you
don't need any inserts Mr. Lang". I like this guy! Of course, I've already
given him $1200 this year and more to come! But what the hey!
latah.
rml
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Bob Lang | TR 6 Guy | Editor: New England Triumphs
Phone: | 617-253-7438 (days)| 781-438-2568 (eves)
Occupation: | ComputerZ | TR fixer-Upper
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