SPECIAL FEATURE: MOTORSPORT
" O F T E N O L D R A C E C A R S G E T M O D I F I E D , U P D AT E D , R E PA I R E D O R C H A N G E D B Y
I N T E R V E N I N G O W N E R S , B U T T H AT S I M P LY WA S N ’ T T H E C A S E W I T H T H I S C A R "
making cylinder heads, cranks, pistons and
gearbox casings, not cheaply, but these parts are
available."
E L E C T R I C S W I T C H
On the recommendation of Xtec it was decided
to replace the original Bosch Motronic electronics
with a Motec system. "There’s nothing wrong with
the Motronic ECU, but if something goes wrong
there’s no way to fix it without sending it back to
Germany. With the investment required to run a
New Zealand-based car in a European championship
it wasn’t worth risking missing a race or
even a whole event due to an electronics issue,"
says Higgins. "With Motec there’s always a Motec
engineer at the track, so it was a no-brainer."
The car uses an upgraded version of Motec’s
popular M800 ECU with a CDi8 ignition box,
connected to an L180 blind logger and a D153
mini-dash. Motec’s Power Distribution Module
(PDM) runs all of the electronics on the racecar,
adding an extra layer of reliability.
"It’s also possible to make fine adjustments as all
the electronics have been brought up to date,"
says Higgins. "This is important because the fuel
used will vary across the world, and it is useful
to be able to tweak the ECU map to allow for
differences in local fuels."
To maintain the appropriate period look, a replica
of the Bosch Motronic ECU box was machined
from billet aluminium. This now houses the Motec
ECU and boost controllers. It was also decided
that, rather than modify and piggyback onto the
original wiring loom, the complete original loom
and ECU would be removed and kept in one
piece, in case it was ever decided to return to the
Bosch system. A complete, new, custom mil-spec
loom was built prior to the car being shipped to
New Zealand.
"We are quite proud of the fact that we have been
able to keep almost the entire dashboard in
the car original and operational," says Higgins.
"The only difference is swapping out one of the
Bosch display units for the smaller Motec version.
All of the warning lights, buttons, switches
and knobs work properly."
Performance is also unchanged. "We’re not
expecting much difference in overall performance
from when the car first raced," Higgins says. "In
qualifying trim these engines are producing
about 900bhp and they typically run at about
720bhp in race trim. They were fuel limited in the
old days, as we are now, so we can’t run full
boost even if we wanted to, because we would
run out of fuel."
Y E L L O W F E V E R
With the engine rebuilt and running well on the
dyno, the car was then shipped to Zealand. Parts
Apart from the Motec display unit the 962’s dash is completely original and wholly operational.
Note the Porsche keyring fob
The engine has been restored by UK-based specialist Xtec, which also suggested the switch
from a Bosch to a Motec ECU
were unpacked, inspected and separated into
jobs.Some required re-coating, others needed
repair or replacement.
With a fresh coat of bright yellow and blue paint
applied, the rebuild began. All of the crack-tested
suspension was re-coated and rebuilt with new
rod ends and sphereical bearings. Uprights were
chromated and rebuilt with new wheel bearings.
New driveshafts were machined based on the
originals and were refitted with new CV joints. New
water radiators were fabricated, but the original
oil coolers and intercoolers were brought back to
as-new condition. All of the oil and fuel plumbing
was replaced, as were the fuel coolers that sit
on top of the massive intake manifolds. Because
these 30-year-old cars are still capable of reaching
speeds of over 300kph, a lot of the original parts
were re-manufactured for safety, including the
brake discs, wheel nuts and the custom titanium
bolts that Porsche used on the 962s. Meanwhile,
the gearbox was fully stripped, crack-tested and
rebuilt with a new crownwheel and pinion and new
bearings.
F L O O R F L AW
The most time-consuming job was repairing the
bodywork and floor. This particular Brun 962 has
several unique bodywork design elements, so
there were no moulds available for new parts.
All repairs had to be done without distorting any
of the original panels. The massive underbody
section was the most difficult to sort.
With the racecar sitting for so long, oil had seeped
back down the turbocharger oil scavenge
lines and had leaked out of the turbos, eventually
32 June 2018