The only time I ever saw seat recession was on the '91 SCCA nation
championship winning TR6. It had 16 to 1 compression and 1475 degree EGT
temps.
We blew a head gasket on the 10th lap and ran the remaining 8 laps
without any water in the engine.
I have heard a lot of talk about installing hardened valve seats in
these engines. In my opinion even modified engines don't need them
unless you are planning on running without water or anti-freeze.
Some recent photos of a TR6 in action.
http://www.gatriumph.com/
http://www.gatriumph.com/GTAevents/2005%20Walter%20Mitty.htm
Mike "Tiger" Munson
....Let's see if the list wants to take part in a poll. Who is
experiencing valve seat recession? Who uses the lead substitute? I'll
keep score. . Dick
Vance, Bill, Mike, and myself claim to have no valve seat recession,
and do not use the lead substitute. Bob said he had some on two valves,
with special circumstances.
Nearly all to all of their miles have been with using unleaded gasoline.
None have said they converted to the hardened inserts.
Unless there are others who know for sure that they have experienced
valve seat recession, and want to tell us about it, and the sole cause
to be related to the use of unleaded fuel, it looks like we can send
this topic to "Myth Busters"!
Dick
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