Miata Mailing List: June 1995, Message #192
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   From: Miq Millman 
Subject: MBG's versus Miata's
   Date: Sat, 3 Jun 1995 16:21:50 -0400

Here's is part two of my reposts from Scott Fisher's literary past.
Again, praise and heart warming comments can be sent to him at
SEFisher@aol.com  (btw, "The Green Car" is Scott's MGB)

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Subject: Four Decades of Auto Repair
Date: Mon, 30 Mar 92 12:02:15 PST
From: Scott Fisher  (now SEFisher@aol.com)

So Saturday morning I had a full day's worth of car work planned
for myself and a couple of friends who would be stopping by.  The
first part of the day saw Miq Millman and, ah, Miq, should I tell
the list what you bought? :-)

Y'see, Miq works at SGI, so I'm used to seeing interesting simulators
from him.  On Saturday he brought over the most interesting simulator
I've seen yet.  It's a very close simulation of a British roadster,
with many of the right sound effects but a few bugs that I think need
to be worked out.  The simulator is called a Miata.

The good parts are the digital sound (16-bit, I think they said).  It
really has a sort of homogenization of MG, Triumph, Alfa and Jaguar,
a sweet rumbly growl that gets your attention from half a block away.
But the simulator stopped short of the actual experience because
there's only the exhaust noise -- real British roadsters have a 
symphony of mechanical sound effects (gear whine, valve clatter,
timing chain clink, exhaust system leak puff, etc.) to go along
with the vroom from the tailpipe.  

We also ran a couple of benchmarks on the simulator and it fails them
in a few serious ways.  For starters, we tried the old let's-wash-the-
engine routine.  Failure 1 was that we were able to put the top up
while seated (and belted) in the passenger compartment.  This is just
plain bad research on Mazda's part; everyone knows that for a Real
British Roadster you have to climb out at least three separate times,
pulling on the hood bow while someone else leans on the Lift-The-Dot
fasteners.  And we didn't break a single fingernail.  Then, once in
the bay of the engine-wash place, we hosed and sprayed and sprayed
and hosed, and after pumping who knew how many gallons of water over
the engine bay, the car started.  Another place where simulator research
failed in a fairly serious way.

On the plus side, though, they did a good job with the oil filter
location.  There is a way to get to it without pulling the engine,
but it requires bending your arm in several axes that nature never
intended, and you will end up scraping and burning yourself while
you get the wrench on the filter.  Note that the only way to do
that is with a little wrench that fits over the end of the filter;
also note that the filter is a very silly size, about the size of
the bottom half of a Coke can.  The ludicrously inadequate appearance
of this part is as British as bangers and mash.

The simulation of British suspension is also only moderately thorough,
but the floorpan is pure MGB, down to the long chassis legs that run
under the seats.  It just looks like an MGB that's been sectioned and
widened about 10" in the middle.  The steering knuckles look an 
awful lot like the Spitfire's units, but the effect is ruined by
having a long shock pass through the upper unequal-length A-arm and
have the spring mounted completely above the upper arm.  Sure, there
are sound engineering reasons to do it this way, but we *are* talking
about a simulator, and it just misses the original mark.

The other crucial ways in which the simulator misses the original is
in a lack of wind noise or chassis flex in operation.  Also, the
frame rate's change curve when you operate the accelerator pedal is
a little wrong, with an exponent that increases instead of decreases
(and the rate is a little quick if you're trying to model the behavior
of a TR or an MG -- the scenery flies by the viewing frustum at a rate
more in keeping with Jaguars than with MGBs).  And they really should
dial some kickback into the hydraulics that work the seat, wheel and
brake pedal.  You don't have the feel of driving on an actual road in
this simulator; for a little work they could give you the feel of a 
bump or of uneven pavement, or better yet make the open chassis flex
or creak when it does so -- there was none noticeable in this car.

[ some text deleted for brevity and subject matter ]

Then it was time for The Green Car.  I've needed for some time to get a
few things repaired in order to pass smog; I've had the belt for the air
pump but it hasn't been installed, and I've had the leak in the exhaust
system that needs two people to work on it easily.  So Chuck pulled the
air cleaner covers while I loosened the air pump.

To no one's surprise, the bracket that was holding in the air pump didn't
want to work with the belt I had for it.  But hey, this is for the MG.  I
took out the bracket -- actually the strip of metal with a bolt hole at 
one end and an elongated slot at the other, used to take up the slack in
the belt -- and realized that the bolt that holds the air pump in place 
should be about halfway between the end of the slot and the fixed bolt hole.

So I calmly found my Dremel and drill and proceeded to make a hole in 
about the right place, figuring that I could Dremel out the slot if it
needed adjustment.  While I was enlarging the hole, I wondered if I 
would have been so nonchalant about making even such a simple modification
before I'd built the race car.

We slipped the bolts through the holes, tried everything on for size --
and it fit as perfectly as if I'd measured it with micrometers.  "You
must live right," Chuck said.  "That isn't it," I replied.  "This is one
of the reasons why I keep a brick from the Abingdon factory on the mantle."

[ more text deleted for brevity and tightness of subject matter ]

Michael and Dustin drove off just after Kim and my own girls arrived
(Torrey approved of the Seven, though this morning she went wild over
a red 911 in traffic -- I gotta have a talk with that girl), and Chuck
and I went back to The Green Car to close it up.  The last piece of 
work was tightening the nuts that hold the downpipe to the header.
We managed to get three of the six to move, but one stud is missing
a nut and the other two were unreachable, so we buttoned it up and I
took it for a test drive.

I was shocked to hear the difference in engine noise.  I had become
used to the popping of exhaust pulses from under the hood, and to the
metallic rattle from the downpipe flanges (which were alarmingly loose
when we tightened them up).  There's so much less noise coming from
under the hood that I wondered if the Miata hadn't let a software
virus loose in my garage: now 80% of the engine noise comes from the
tailpipe, instead of 50%.  And it's not finished yet; I'll probably
go to the extreme of paying a muffler shop to install the ANSA setup
I've got in the garage, and to replace the downpipe gaskets while 
it's up on the lift.

There's also no difference in performance, at least no discernible
difference, now that the belt is back on the air pump.  There is,
however, a slight squeaking noise from the air pump's bearings.  I
think I'm going to be glad I have a spare in the garage.  Are the
pumps rebuildable?  Can I try spraying some light oil into the
pump's air intake and see if that helps things any?

As the day wound to a close, I realized that I had worked on four cars
that day, and furthermore that I had worked on cars from the Sixties
(the Chevelle), the Seventies (the MGB), the Eighties (the GTI) and
the Nineties (the, uh, simulator).  Four decades of automotive design.


--Scott



Subject: British Racing Stuff
Date: Wed, 01 Apr 92 11:58:01 PST
From: Scott Fisher  (now SEFisher@aol.com)

It's looking more and more like a real racing team every day.  Miq
Millman, Chris Kent, and I are forming a sort of pan-British sports
car team to compete in the regional championship for the Sports Car
Club of America's Solo II (autocross) series.

Miq, of course, brings his experience with Austin-Healeys, as a 
long-time member of the Sprite-Midget Owner's Group (SMOG), as
well as owner of two (and a fraction) very sharp Sprites.  Chris
represents Triumph, with his GT6+ and the soon-to-be-completed
restoration on his TR-4A.  I, of course, uphold the honor of the
Octagon with my various exploits in MGBs.  Given the British 
nature of our team, I probably should bring tea and cakes to the
track when we're competing.

Last Saturday saw our first work on this year's race car, when I
put a sump's worth of synthetic oil in the car; the engine is still
new enough that it didn't leak all over my driveway as I poured it
in, and oil pressure looked good at 70 psi at full throttle and 30 
psi at idle.  Chris dropped off two quarts of Redline MTL (manual
transmission lubricant) so we can protect the synchromesh in the
gearbox; later we'll figure out what to put in the differential to
work best with the limited-slip differential in there now, but the
car has few enough miles on it that we can wait for that.

Miq painted the Panasport rims we picked up last week, and they're
now a very Minilite-like dark grey metallic.  Since the race car is
a two-seater, I'll be driving the Biscuit Tin of Steel as a support
vehicle; yes, I'd love to take the MG, but the GTI is a better choice
for bringing mounted tires, an air tank, a jack and our tools, not
to mention the folding table and some chairs.

The race car is white, so the question now is whether we go with 
green trim to look like the old TAG-Williams F1 cars like the one
Alan Jones used to win the 1980 World Championship, or red to 
look like the many McLaren chassis that have driven to victory 
lane and provided English constructors with the crown over the 
years.

The only problem with this is the car itself...

It's a Miata.

--Scott "Nihon-go ga `God Save the Queen' hanase-masuka?" Fisher


-- 
Miq Millman   mmillman@ptdcs2.intel.com	  503 642 6139   (Aloha site)
AL4-55  Intel, 5200 NE Elam Young Parkway, Hillsboro, OR 97124-6497
See also miq@teleport.com