I ran an MGB GT for 8 years here in Canada in summer and winter and I do
not drive "soft" but neither do I thrash the engine. The car's body
collapsed under the weight of rust but the engine went into my friends car
and is still smooth, lusty and pulls hard (sound like a girlfriend I
had). It never saw leaded fuel! I then tested Shell Canada unleaded
over a years driving an Austin Healey - they paid for everything. The
engine was measured with a special jig made by Shell to determine wear -
result? no signs of valve seat recession. I believe that hardened seats
are great but not always required - unless you intend to thrash the engine
(in which case something else will give too). If you look around you will
see the marketing of many not really needed products from Nike, Coca Cola,
Gap, MacDonalds, Disney etc so why should fuel additive companies be any
different by promoting a false image that enhances their sales. - CONSUME
DUMMY - it makes me rich!
At 11:52 AM 12/31/01 -0600, Rocky Frisco wrote:
>Lawrie Alexander wrote:
> >
> > Maynard, Maynard, Maynard............
> >
> > So much good advice from your keyboard this year, and then you wait
> till the
> > very end to post this! Empirical tests have proven that hard seats prevent
> > valve seat recession. Just about every qualified mechanic who has worked on
> > cars that were not originally fitted with hard seats knows that they are
> > necessary to prevent valve seat recession. The additional cost during a
> > valve job is so small that, unless the finished rebuild is going to sit
> in a
> > trailer queen that never gets used, it's truly false economy not to have it
> > done.
> >
> > I hate to close the year on a critical note, but hardened exhaust valve
> > seats are a must when doing a valve job - if they have not already been
> > fitted during prior work on the engine. You may choose, of course, for
> > whatever reason, to find them unnecessary, but please don't try and
> convince
> > other neophytes to the world of engine rebuilds that your choice is the
> most
> > sensible!
>
>I've been building racing engines since 1964 and I'm beginning to
>get an opinion on the hardened seats question. The present engine in
>my Cooper S is a 1967 Cooper S Engine that came out of a car that
>raced at Sebring way over 30 years ago. I installed an APT 286
>scatter cam when I built it. It has a very free-flow breathing
>system with a single 1.75" HIF SU on it and an LCB exhaust system
>with a free-flow silencer. I use a 3:44 diff and standard 4-synchro
>trans. That puts me over 4k rpm when cruising on the motorway. Since
>the original build, I've done an 800+ mile round trip from Tulsa to
>Saint Louis and back, as well as many 200 mile round trips. I drive
>fast and hard because it's fun (and I have four spare power units
>stored for emergencies).
>
>I've had the head off three times for various reasons since then and
>have seen no evidence at all of seat recession or valve wear even
>though we haven't had leaded fuel here for decades. I have spare
>heads in the garage, so my plan has been to wait until I see damage
>beginning to manifest from the crap fuel, then to have the hardened
>seats installed. So far there has been no damage, so no need.
>Compression remains very good and very even.
>
>I have also heard horror stories about recession and wear using
>unleaded, mostly from friends in the UK, I wonder if the petrol
>formulations are quite different.
>
>The Victor MGB-TF is up on blocks waiting for some relatively warm
>weather to get his new clutch TOB installed. One of these days I
>will be building the spare B engine up to high performance specs to
>install in the Victor, so I'm very interested in this discussion.
>
>-Rock http://www.rocky-frisco.com
>--
>Red Dirt Rangers (Rocky on piano): http://www.reddirtrangers.com
>JJ Cale Live (w/Rocky): http://www.rocky-frisco.com/calelive.htm
>The Luggage Fan Club: http://groups.yahoo.com/group/luggage-fans
>
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Regards
Barrie
Barrie Robinson - barrier@bconnex.net
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