On the topic of unleaded fuel, is anyone relatively confident that unleaded
petrol can be used with no detriment to the spit, as certain car magazines
state that it cannot be used.
Craig Skitt
Inca Yellow 1976 1500 O/D
W.Mids
England.
>From: Craig Smith <CraigS@iewc.com>
>Reply-To: Craig Smith <CraigS@iewc.com>
>To: "'Barry Schwartz'" <bschwart@pacbell.net>, triumphs@autox.team.net
>CC: spitfires@autox.team.net
>Subject: RE: Of interest to concerns of unleaded fuel usage
>Date: Tue, 16 Nov 1999 08:22:47 -0600
>
>My understanding also on the Stellite valves are that they index themselves
>with each opening. Index meaning they rotate so the seat will not see the
>same part of the valve on each closing. The above also tainted with age and
>old Miller Lite use.
>
>
>-----Original Message-----
>From: Barry Schwartz [mailto:bschwart@pacbell.net]
>Sent: Tuesday, November 16, 1999 8:10 AM
>To: triumphs@autox.team.net
>Cc: spitfires@autox.team.net
>Subject: Of interest to concerns of unleaded fuel usage
>
>
>
>I was reading a PDF copy of the British Leyland Motor Inc., service
>division, dealer training booklet, concerning 1970 emissions data and on
>page 7, it states:
>
>To conform with the emission control standards, imposed by the federal
>authorities, the following engine modifications are incorporated.
>
>1. Exhaust Valves
>Stellite faced exhaust valves are fitted to maintain effective valve
>seating between servicing intervals.
> < snip >
>
>What this means for those of you with 1970 and later vehicles is that you
>needn't worry about using unleaded fuel in your vehicle. From what I
>remember (which is becoming cloudier with age :-}) this is one of those
>changes made to preclude valve wear when unleaded was introduced. Stellite
>(trademark) for those of you who might be interested, is a cobalt-base
>alloy with chromium and other metals; very hard; used to make cutting tools
>and for surfaces subject to heavy wear
>
>I seriously doubt that heads destined only for the USA were the only ones
>fitted with these valves, as I imagine the logistics of determining which
>heads/engines are destined for what country would be more expensive than
>fitting them to all cars. And I'm sure hardened seats would also be
>fitted, as what would be the point of fitting harder valves just to let the
>valves beat the seat to pieces, although I could be mistaken here
>
>Just thought that might clear up a few things (or maybe muddy the waters
>even more ;-0 ??)
>
>
>Barry Schwartz (San Diego) bschwart@pacbell.net
>
>72 PI, V6 Spitfire (daily driver)
>70 GT6+ (when I don't drive the Spit)
>70 Spitfire (long term project)
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