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Re: Best Carbs for MG???

To: mgs@autox.team.net
Subject: Re: Best Carbs for MG???
From: Scott Fisher <sefisher@cisco.com>
Date: Sun, 02 May 1999 22:00:45 -0700
Lawrie Alexander says:

>  In 24 years of working on MGs for a living, I have to say that
>  I've never yet driven one that drives more nicely than one 
>  fitted with SUs.

Well, now I'm doubly sorry that the #2 gudgeon pin came loose and
wrecked that cylinder, you would have liked The Green Car in its final
configuration. :-)  

I'd love to take all the credit for that particular conversion, but I
can't.  (I'm pretty sure I *can* take credit for the gudgeon pin coming
loose, as I put those pistons in, and it was my foot on the gas of a
too-cold engine that caused the fatal knock in the first place... it's
very depressing to spend hours building something with your hands, only
to spend seconds destroying it with your foot.)

The Weber probably isn't an easy conversion to make, and I can easily
believe it would be a less successful installation on a stock MGB.  Mine
was far from stock by the time the Italian carburettore was bolted on. 
The block came straight out of my old SCCA driver's school car, the head
was basically a shopping-list special -- name a piece of TRS and it was
on that head.  (Heck, that cylinder head cost more than my wife's sewing
machine! :-)

The porting, polishing and chamber matching was done by my good friend
Chris Kantarjiev, who is not only brilliant but also completely
anal-retentive, two characteristics that combined to lead to a head for
which the surfaces of the combustion chambers looked as though they had
been engine-turned, like the dashboard on a Bugatti.  Rimflo valves,
Viton seals, ARP studs, silicon-bronze valve guides that Chris
bullet-nosed on a lathe, and porting profiles that he basically cribbed
from Vizard's book and multiplied by 1.5 to get to work on the 1800... 
And there was the end-for-end balanced 18GB angled big-end rods (which
required relieving the inside of the crankcase to clear the cam boss),
the micropolished crank (which was the one suspect piece, it coming out
of the 18V block and therefore not made with the EN19B material of the
earlier engines), the Powermax pistons in stock 8.8:1 configuration
under a head giving just about 9.5:1 total compression, running a Piper
Blueprint 285 cam.  Not a stock car, but very possibly a car that would
have outrun the factory Le Mans cars in the Sixties.  

And the Weber itself was set up by Mark Bradakis (and anyone on this
list who says "who?" should buy the rest of us a Klisterbrau), via
email; though it ran beautifully when I installed it, Chris and I spent
about 10 minutes dialing the idle circuit for smooth idle and good
pickup.  The mains, emulsion tubes, and chokes were close enough to
perfect for me.  Don't remember the numbers, and that carb is now (with
different brass bits) on a friend's vintage racing Bugeye Sprite up in
Oregon.  (If you race SCCA in Oregon, you know Jeff, or at least you
know who he is -- he's the one in charge of whether you get on track or
not.)

We put the Vericom performance computer on that car and came away with
57.5 bhp per 1000 lb, at the rear wheels.  In a 2100-lb car that'd be
good, but with easily 400 pounds of me and Chris in it as it was
tested...  I was satisfied with the performance.  And on that car, 'd
given up originality and even reliability in the name of performance. 
(Of course, it *did* look about like the picture in the back of the
Special Tuning supplement, with the stock cast-iron manifold -- suitably
relieved inside to keep the gases flowing, ask me about that some time
-- and the 45DCOE.  If it's good enough for Syd Enever, it's good enough
for me.)

So I'm easily convinced that the 45DCOE was the icing on a cake of great
care, diligence, and attention to detail.  (Maybe not quite enough of
the latter, given the fact that something came loose in the bottom end
about once a year for the last three years I had that car; sure, that's
part of the game for racing, but this was meant to be my daily driver.) 
I can easily believe that simply bolting that on where the twin SUs came
off, especially if the jets/chokes were not selected by someone with as
intimate a knowledge of performance cars and Webers as Mark evidently
has, would result in a car of questionable smoothness.  Which proves the
saying about knowledge being power -- and also that it isn't just what
you know, it's who you know.  Thanks, guys.

Still -- the 1275 Midget I'm getting shortly will keep its SUs for a
long time to come, and may never see that 45DCOE.  Why?  Because I've
stopped people by the side of the road whose M.G.s had quit on them, and
with nothing but fingertips and ear I've "un-fiddled" their SUs and got
them running again.  Because the only time on any car tour that I've had
a car quit running, it was because of a piece of dirt holding one of my
HIFs shut and keeping the gas out, and a quick drop of the bottom panel
and a rap on the float valve got me going again.  

And fundamentally, I'll synchronize and dial in my SUs for much the same
reason I run Castrol in all my cars -- because Col. George Eyston was a
director of Castrol while he was driving all the M.G. EX cars to record
speeds on the salt at Bonneville.  As my wife said about my first M.G.,
"But the SUs are part of what makes him an M.G.!"

I mean, if tradition and heritage and the inherent rightness of things
don't count for something in our M.G.s, we might as well all ride the
bus or drive Hyundais, right?

 --Scott "Safety really REALLY Fast!" Fisher
   Sunnyvale, CA

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