A good friend of mine (Darryl Murphy, author of Carrera Panamericana) wrote
this article for Road & Track. Unfortunately they turned it down. I thought
you folks might like it.
John Price
BRM V-16 being redeveloped
"The new Model 15.1 retains the marque's most memorable features whilst
showing some significant and worthwhile regressions."
By Daryl Murphy
GREATER CHORTLE, LINCOLNSHIRE.-A group of UK club-racing entrepreneurs has
announced the resurrection of the BRM (British Racing Motors) marque with a
redevelopment of the 1948 BRM Type 15 V-16 Grand Prix car using current
technology and contemporary materials. Undaunted by technical realities, the
new company, Babbitt Regressive Mechanisms (BRM), has assured investors that
while the new car may be slower, heavier and more difficult to handle, it will
nonetheless recapture the spirit of BRM.
Founding Director Sir Harold "Bunkie" Henroid stressed that to keep costs at a
reasonable level the company would be using the 60-year-old existing parts
inventory whenever possible, and assured British vendors that their components
would enjoy favored status.
We spoke with Mr. Sidney Bustlethwaite, former BritishRail boilermaker and now
Chief Project Engineer at BRM. Bustlethwaite was responsible for developing
many original and creative design flaws for his former employer, and has
incorporated those into the new program-referred to as the Type 15.1 car. He
assured us, however, that all fundamental weaknesses of the original BRM had
been retained.
Among the new measures is that of a variable steering load system that
encourages the driver to keep steering in a centered position. This feature
was added after early prototype testing revealed that, while drivers of
average strength were able to achieve up to a quarter-turn wheel deflection,
the action produced no appreciable variation in the net track of the car.
It was additionally discovered that most of the past racing incidents that
were not predicated on engine failure could be traced to suspension or
steering problems, so costly and unnecessary linkages in the worm-and-hook
steering and dragging link suspension were removed wherever possible. That
exercise produced a valuable reduction in weight, as did the redesign of the
steering to a simple system that allows the entire front axle to pivot about a
central vertical pin, an idea that came to Mr. Bustlethwaite after visiting
the Soap Box Derby Hall of Fame in America. In addition to the new pulley and
bungee cord linkage, the leaning of the driver's body is the primary means of
directional control.
The central focus of the original Model 15, of course, was its complex
1.5-liter V-16 two-stage supercharged engine that was designed to develop 600
horsepower at 12,000 rpm. In keeping with the philosophy of the marque, the
enigmatic new Type 15.1 engine employs 1,870 moving parts. The total count-an
additional 308 more than the Type 15 design-is higher because of the
adaptation of a desmodromic valve system, but engineers found a trade-off by
eliminating several dozen crankshaft counterweights.
Unfortunately, early test runs showed an excessive amount of vibration in the
prototype engine in the 500-12,000 rpm range, so maximum revolutions were
increased to 18,000, slightly narrowing the useful power band. At revs below
peak readings on the new engine, power drops off quickly, with 173 hp
available at 16,000 rpm, diminishing to 45 hp at 11,000 rpm and nil below nine
thousand.
Because it was necessary to get high engine speed in order to move the car
from a static position, clutch and driveshaft failures were common on the Type
15. To correct the problem, BRM engineers have cleverly adapted a four-speed
transmission and drive system from a 1948 BSA motorcycle supplemented by
10-speed Peugot derailleur, effectively providing 40 forward speeds.
However, the new BRM has answered a question that has been puzzling engineers
and drivers for many years by working under the hypothesis that it is noise
that makes the car run. Bustlethwaite explained that sonic waves created by
the engine and amplified by the .010 aluminum bodywork cause the air molecules
to oscillate at atomic frequency, which is then turned into torque that is
transmitted to "the driving arm," as he put it.
"This theory can be demonstrated by closing the throttle," Mr. Bustlethwaite
explained. "The bloody thing just stops dead in its tracks! And if you need
more proof," he continued, "look at the Ferrari Formula One car. It makes a
lot of noise, and look how fast it goes!"
Wellington Moss, a former BritRail engine driver and the step brother of a
second cousin of Stirling Moss' grandfather's paternal uncle by marriage, is
the Chief of Testing at BRM as well as part-time signing instructor at the
company's Academy for the Aurally Impaired. He concurred with Mr.
Bustlethwaite.
"Bloody 'ell!" he shouted, "When yer in the cab [as he termed it] an' yer gets
yer steam up, yer can't 'ear bloody nuffin!"
Mr. Moss explained that ergonomic design measures applied to the race car
ensures that long-term deafness does not encourage lethargy. Orthopedic
consultants designed a seat that allows full three-axis sliding movements
which, when combined with the casual steering action and breakaway brake
linkage, keep a driver awake and fit. Special noise-retention material fitted
in the cockpit and on the seat allows drivers to relate ear pain directly to
engine power, thus eliminating the need for instrumentation.
We were offered the opportunity to test drive the Type 15.1 at the company's
facilities on Greater Chortle Regional Aerodrome, an abandoned RAF facility
adjacent to the BritRail regional office. The test had originally been
scheduled at Nurburgring, where the car could stretch its legs on long
straightaways, but BRM has been banned in Germany during avalanche season.
After a four-hour briefing concerning some of the anomalies of the BRM, we
climbed into the roomy cockpit. The 28-in. steering wheel is nostalgic yet
unwieldy, and the BSA gear selector mounted on the left and derailleur shifter
on the right fall readily to hand(s). The starkly simple yet elegant
instrument panel with engine-turned fascia is fitted with only one gauge, a
tell-tale dB (decibel) meter.
Because high crankshaft speed is required to ensure continuous operation of
the engine, an RAF turbine GPU (Ground Power Unit) was towed into place and
connected. It cranked the BRM's engine to 10,000 rpm, whereupon the fuel
switch was engaged. In about twenty-five or thirty seconds, the Lucas ignition
came to life and the V-16 screamed to speed. A glance at the meter indicated a
reading of 205dB (a quick calculation showed that to be 1150 hp at 114,000
rpm).
As earlier advised by Moss, warmup was completed in a few seconds, governed by
the density of steam emanating from the radiator cap. We slipped the
transmission into first gear and the Peugot to eighth and engaged the clutch
carefully. Wisps of smoke arose from the large unlimited slip 6.00 x 21 rear
tires as we chirped and shuddered away at a relatively low power reading of
160 dB.
Quickly up to speed on the mile-long runway, we saw 249 dB on the dial, which
calculates to 1422 hp and 1170 mph, matching the factory's (although not the
public relations department's) predictions. We later learned through a series
of letters from angry townspeople that we had achieved vibration amplification
of 500 CPS, proving the new Type 15.1 the most efficient converter of fuel to
noise since the Titan rocket.
Our test was cut short after a slow turnaround at the end of the runway
followed by an abrupt and overenthusiastic application of throttle that caused
the entire BSA drive system to fail and be summarily distributed over a large
part of Lincolnshire.
Bustlethwaite assured us that it was not an unexpected occurrence, and that
BRM is already at work affecting a modification that involves the traditional
English engineering solution of fitting dual components, thereby not only
increasing the strength of a given assembly, but doubling its chances for
failure. However, he admitted, BRM may be obligated to turn to American
manufacturers Harley-Davidson or John Deere for the more heavy-duty
components.
We returned to BRM's offices convinced that the new Model 15.1 retains the
marque's most memorable features whilst showing some significant and
worthwhile regressions.
The company is not, however, resting on its laurels. Plans are already
advanced for a new three-liter, three-stage supercharged model in a W-36
configuration, and noise tunnel testing is underway.
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