british-cars
[Top] [All Lists]

Engines

To: alliant!alliant.alliant.com!british-cars@EDDIE.MIT.EDU
Subject: Engines
From: sgi!abingdon.wpd.sgi.com!sfisher@EDDIE.MIT.EDU (Scott Fisher)
Date: Wed, 22 Nov 89 15:46:25 PST
>Greg Nagy writes:
>
>>   As for the Agricultural background . . .
>>I don't remember if it was the A90 or the BMC C-type engine, but one of
>>the 2 engines were designed for use in London Buses. 

Well, you *could* be confusing things from a very unflattering
reporter's comments about the revised C-type engine that was
used in the MGC.  He said that it "appeared to have been designed
for an agricultural application by an engineer who had been
transferred against his will from the marine diesel division."
The MGC's engine was disappointing, to Abingdon and to the 
press alike, largely because it was a lot heavier than BMC
had told Abingdon it was going to be.  This wrecked their
carefully planned front suspension (with torsion bars and
tubular shock absorbers), destroyed the car's balance, and
forced them (because of an additional 4" or so of height)
to add the "power bulge" in the C's hood.

>>The A90 could also be found in Austin Taxis.
>
>Actually, the engine for the A90, a 2.6L 4 cylinder motor, traces its
>design origins to a British Jeep built during WW II.  When Donald Healey
>came along, Austin had a considerable excess of the units.  Mr. Healey
>incorporated the engine unchanged into the Healey 100.  

Not according to my sources when I was researching the article
for _Victory Lane_.  According to what I was able to determine,
they changed cam timing, compression, and carburetion.  It
*still* has a low redline (what is it, something like 4800 RPM?)
but it produces bloody great amounts of torque.  I love the feel
of that motor, especially with the electric overdrive clipping
in and out as you tool through traffic.  What a car.

Another carryover: the transmission used in the Hundred was from
a truck application.  First gear was so low (numerically high)
that the Healeys installed a blanking plate to keep you from
being able to shift into it; this meant you started in second
gear, which is why they installed that smooth Laycock-de Normanville
electric overdrive on the back of the 'box.  Also, there wasn't
room in the sports chassis for a remote-control mounted on the
back of the gearbox, which meant that the gear pattern is 
reversed right-to-left.  This means you shift a Hundred like
this:

                  4

          2
          |_
          | |
          3 1


where 4 represents the dash-mounted toggle switch for the OD. :-)

Apparently, it was common for people to remove the blanking
plate from the original first gear.  It was also common for 
people to break first gear within several weeks of making
this change, because of the additional HP of the revised
motor.  The Healeys weren't stupid.  In 1956, the 100 was
updated slightly (from type BN1, 1953-55, to BN2, if you're
keeping notes) and received a proper four-speed trans, revised
brakes, and a very slightly different dashboard treatment.
The styling was unchanged, thank goodness.

The 100-M version of this motor got even more changes, including
higher-compression pistons (the service instructions on the A90
engine say not to raise the compression by shaving the head, BTW),
an even lumpier camshaft, and a cold-air box that brought high-
pressure air from the grille to the carbs.  It also got uprated
brakes, sway bars, and shocks, as I recall, not to mention that
amazingly butch leather hood-strap and the twin rows of louvers.
Those were the cars I admired most at the Healey club meets.

The ultimate 100 is the 100S, a specialised racing version 
named in honor of Sebring.  Some specs: top speed 132 mph, 0-60
7.5 seconds, four-wheel disc brakes, integral oil cooler (and a 
neat trick too -- they mount the traditional canister oil filter
up behind the grille, in an aluminum housing just covered with
cooling fins!), and a grille like a 3000s but without the 
necessary "power bulge" in the bonnet.  There are a couple of
these making the rounds in vintage racing.  

>When BMC was formed
>about this time, it found itself with many overlaping models and components.
>The 2.6L 6 cylinder C-type engine was designed to replace various engines
>from different marques with one common motor.  As a result, the A-H 100
>became the A-H 100/6.

Right, and my friends with "100-4s" like to point out that
the Healeys never really made a "100-4," they made a 100 
which was followed by a 100-6.

>As a side note, the Healey Motor Car company had been using a 2.4L DOHC,
>4 cylinder engine from Riley.  They went with the Austin engine because
>they were afraid the engine might be phased out of production.  After
>Riley became part of BMC, they continued to produce the engine, even beyond
>the introduction of the C-type engine(I think).  It's fun to wonder what
>the Healey 100 would have been like with the Riley engine.

I know at least one person who salvaged a wrecked 100 that had
no motor in it when he acquired it; he installed the Rover/Buick/Etc
aluminium V8 along with a TR8 5-speed transmission.  I followed
him from dinner back to the hotel one night during California
Healey Week a year or two ago.  At one point it started making 
this interesting noise; then it got real small real fast.

Me?  A black '55 100M, with red inserts on the fenders, black seats,
a red dash and red piping.  And glass goggles to keep the bugs out
of my eyes when I drive with the windscreen folded.

(Oh, you think I *have* a car like that?  Not yet...)






<Prev in Thread] Current Thread [Next in Thread>