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Torque, NWI cam, Cats, Pretty cars

To: mgs@Autox.Team.Net
Subject: Torque, NWI cam, Cats, Pretty cars
From: Bill Eastman <william.eastman@medtronic.com>
Date: Wed, 23 Dec 1998 11:53:12 -0600
Someone said that you couldn't put as much torque on an MG removing the
front nut as it puts out.  Few MG's put out more than 100 lb-ft of torque
yet it is quite easy to exceed that number with a breaker bar and cheater
pipe.  A typical mechanical design  for a max 100 ft-lb of alternating
fatigue loading would be to first double it to take into account that
steel's fatigue strength is about half of its ultimate tensile strength. 
Then one would add a factor of safety- say three.  A crank would be
designed to withstand 600 lb-ft of static loading torque.  With a 3 ft
breaker bar you would have to pull with 200 lbs of force to create this
much torque.  Doable but not probable.

I purchased an NWI fast road cam last spring for the MGA.  So far so good. 
The A has a little more power at highway speed yet remains quite driveable.
 I am still not winning many stoplight drag races though ;-)

Putting a catalyst (I bet you though I was going to bring up the other cat)
on a carbureted car without mixture feedback will clean up the exhaust but
the odd are that it will run VERY hot.  Don't park over and dead leaves. 
When tuned to give good power on acceleration, SU's run very rich at
cruise.  Don't be surprised if you can see the cat glowing cherry red at
night.  If you lean the beast out enough to make the cat happy, then it you
will lose a lot of acceleration since the mixture will be too lean for best
power.

The cold engine squeal is most likely a hung starter drive.  These are
supposed to run without oil but if your MG is typical, some oil escapes the
rear seal and finds its way to the starter drive.  This oil gets stiff when
cold and can hold the drive engaged until the heat from friction thins it
out.  The same heat from friction is wearing out the starter bushings so
this is not a good thing.  Pull the starter and clean the Bendix. 
Lubricate it with a dry lubricant (graphite, Pedro's Extra Dry, Silicone)
and the problem should disappear.

I don't know why we even debate this.  The list has already established
that the MGA is the best looking car ever built.  Maybe this fact should be
included in the FAQ so that new comers will be properly enlightened prior
to airing comments to the contrary.  TF's and XK's are nice but the A is
the top of the heap.  Why do you think they called it an A in the first
place?  This fact was fully appreciated when I drove through Canada this
summer.  A native would say,  "Nice car, A?"  To which I would simply reply
"Yes, it is."

Regards,
Bill Eastman
61 MGA settled in for 5 months of beauty sleep.
58 XK150 settled in for the 20th century.

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