|
The car was designed and constructed as a one-off special, during
1951, in South Australia by Murray Trenberth, using a Vincent Black Lightning V twin
engine specifically imported from the Vincent factory for the car. This well-known vehicle in Australian racing circles had
considerable success from its first outing in January 1952 where it took fastest time of
the day at the Collingrove Hillclimb in South Australia.
Period successes (1952 - 1960) included: 1st South
Australian Hillclimb Championship; 2nd Australian Hillclimb Championship;
Outright Lap record holder, Port Wakefield Circuit in South Australia; 5th
Australian Grand Prix in 1955; 1st Reno Trophy Altona Circuit ,Victoria 1956;
and over 150 race, sprint and hillclimb wins. It was the last air-cooled car to compete in
the Australian Grand Prix (1962). |
|
The
Trenberth was raced by Murray until it was purchased by the late Don Willison, a
well-known Australian Speedway Sidecar champion, in 1960 and raced by him until his death
in 1973. The car then passed through 3 other owners
before being acquired by Kerry Horan in 1990 who competes regularly in hill climbs and
races.
The cars specifications were quite advanced for its day. It has a tubular ladder chassis with 3
diameter tubes weighing 35 lbs bare with a wheelbase of 86, front track of 50
and a rear track of 49. Only front bodywork was used, built in alloy and no rear
bodywork was ever fitted. The original paint
used, according to Murray Trenberth, was household Spartan full gloss enamel, bought from
the local hardware store. The car still
retains its original burgundy body colour with all other components being finished in
black.
Murray fabricated the front independent suspension with unequal
length wishbones, the lower ones being constructed of square tubing and the upper ones
fabricated from sheet metal. Coil springs and
fabricated uprights are used and the stub axles are connected to the wishbones by
ball-joints. A tiny rack and pinion steering was made. The independent rear suspension is
by swing axles, chain drive (no differential), tubular radius rods and is suspended on
rubber bands. The rubber bands were originally
cut from 6.00 x 16 inner tubes and today bands from truck tarpaulin fasteners
are used. All of the rear suspension and
drive components were specially fabricated including tubular swinging axles and the rear
hubs which use large diameter roller bearings. Tubular shock absorbers are fitted all
round. There are twin leading shoe brakes with 10 x 1 ½ alloy drums on all
four corners giving a relatively large brake lining area. All
of the brake components were specially made including cast alloy brake shoes, dural wheel
cylinders and stainless steel pistons. The
brake design, according to Murray, was based on photographs of the brakes of pre-war
Mercedes Grand Prix cars. |

A Vincent Comet single (498cc) modified to Grey Flash specifications with a Norton
gearbox was also used for different events. |
Nickel chrome brake drums were cast
integral with specially designed alloy wheel centres.
The chromed steel wheel rims are copies of early 1950s Renault wheel rims and bolt
to the wheel centres. A new factory racing
Vincent Black Lightning V twin (998cc) engine and gearbox was ordered from the Vincent
factory through the Adelaide Vincent agent, Sven Kallins and fitted to the car from new. A modified clutch was used after the original
Vincent clutch exploded. The motor was
modified very early on to overcome the problems encountered with crowded rollers
identified by the speedway Vincent sidecars. Local
Adelaide replacements of the crankpins, bearings and main shaft proved successful for long
running reliability. The engine, running on
methanol, and using a 12:1 compression ratio, developed 80 bhp and in a car weighing only
500 lbs, gave a ratio of 320 bhp per ton and excellent performance. |