| Nissan had lost the 1967 Japanese Grand Prix, the best they
could manage was a second place behind the winning Porsche Carrara 6. The
ex-Prince Motor Company engineers at Nissan, headed by Shinichiro Sakurai,
had no intention of loosing again and set about building a vastly different
car than the previous Nissan R380-II.
In 1966 the North American Can-Am series had begun as a challenge
series between Canada and the USA and was run under the FIA Group 7 regulations.
The Group 7 regulations were rather interesting, in fact there was hardly
any regulations at all. Group 7 allowed for unlimited engine sizes and
virtually any aerodynamic devices you would like to run. It was only one
step away from being a "do what you like" formula. The formula was completely
mad and ended up with some truly ridiculous machines racing. This whole
concept appealed to Shinichiro Sakurai, who was not averse to carrying
out some oddball engineering ideas himself in the past. There was nothing
to stop Nissan building a Group 7 car, as the Japanese Grand Prix was sanctioned
by the FIA.
This now gave Sakurai carte blanche to do whatever he wanted, and he set
about building himself, with the help of his engineering team, what would
basically be a Japanese Can-Am car. Under the previous regulations raced
under in Japan all cars had to have a roof, and convertibles had to run
with a hardtop in place. The first version he worked on was an evolution
of the old R380-II. It was the same closed coupe design, but now with a
revised rear section that incorporated a Kamm tail cut-off similar to that
of the McLaren Can-Am car. The Group 7 regulations allowed for open top
cars, but Sakurai continued with the coupe format.
All that changed abruptly when word got out that Toyota was
starting work on their own Can-Am style Group 7 car, rather unimaginatively
called the Toyota 7. And not only was the Toyota 7 a Can-Am style car,
it was an open top as well. This caused Nissan to rethink their coupe design
and late in it's design the roof section came off to make it an open top
racer as well. No intergrated roll bar was included, all the car had for
roll-over protection was a single tube behind the cabin.
In the Can-Am series Jim Hall had been experimenting with
high-set rear wings on his Chaparral cars, and Sakurai decided to try these
on the R381 as well. The novel wing arangement on the R381 consisted of
a rear wing that was in two sections, with the left side being seperate
to the right. These two wing sections were attached to hydraulic actuators
that could change the angle of the wing. As the car went through corners
one wing could stay flat while the other side tilted, this allowed the
car to generate downforce only on the side of the car that required it
in that corner. The film of the 1969 Japanese Grand Prix shows amazing
images of the cars going through the esses at Fuji as the wings change
position again and again through the corners.
If you are racing in a category that allows for an unlimited engine capacity
there is no point playing aroung with 2 litre six cylinder engines, especially
if you have a design team itching to seek out brave new ideas. And brave
they were, because the engine they set out to build was a 6 litre V12.
This was something way beyond anything they had attempted before, and full
marks must be given for even attempting such an outrageous project, keeping
in mind the fact that this was from a company that ten years ago could
manage nothing better than a side valve four cylinder engine that produced
37hp. In the end they weren't able to get the V12 ready in time for the
1968 race, and panic set in. The car was ready, but they had no engine
to put in it. Rather than give up, Sakurai decided to source an engine
from another supplier as a stop-gap measure. Pride would stop him from
approaching one of the rival Japanese manufacturers, plus none of them
had an engine anywhere near powerful enough for what he had in mind. Sakurai
decided to head for the home of Can-Am racing and went to the United States
to look for an engine. Whilst there he was introduced to Dean Moon from
Mooneyes, who offered to supply him an engine, or three to be precise.
The engines he came back with were vastly different to the high-tech V12s
he had planned the car around. Dean Moon provided him with three highly
tuned and modified Chevrolet V8s, each engine was 5451cc in capacity and
produced 450hp. This was well short of the 600hp he was hoping for from
the Nissan V12, but still a massive jump in power over last year's 220hp
6 cylinder engines.
Even with 150hp less than hoped for the Chevrolet powered
R381 had enough power to destroy the Toyota 7 with it's 300hp V8. But was
it enough to beat the new Porsche 910 that was also entered in the 1968
Japanese Grand Prix ? Nissan entered three R381s in the race, there was
also three of last year's R380-II cars, three Toyota 7s and several Porsches.
At the end of the day a Nissan R381 wone the race, with a Porsche 910 coming
second. Nissan also scored third, fourth, fifth and sixth places, while
the best Toyota could manage was eighth. This was the first and last time
Nissan would enter a factory prepared car with someone else's engine, and
they now had a year to get the V12 sorted out. Next year's car would be
the Nissan R382.
No point in winning a race if you aren't going to brag about
it, especially when you have just beaten a new Porsche 910
A nice front-on shot of the Nissan R381 showing it's two
piece wing moving during cornering.
Nissan R381 Specifications
Length - 4410mm
Width - 1790mm
Height - 1255mm
Wheelbase - 2470mm
Weight - 836kg
Top speed - unknown
Transmission - unknown
Model - Chevrolet
Pushrod 90deg. V8
Capacity - 5451cc
Bore & Stroke - unknown
Power - 450hp@6000rpm
Torque - unknown
Compression - unknown
Carburettors - unknown
Final Drive - unknown