Hi there Skip,
I never thought that I would ever find out there were other people
interested in the Marina apart from the local scrap metal yard. Here’s the
background as to why a Marina. (You can use whatever info you want, and if
you want more detail let me know.)
For me the choice of a Morris Marina was pretty logical. I had been racing a
1971 MGBGT in the Standard Production Sports & GT class here in NZ for
several years. Originally in club events and moved up to a classic racing
series called the BMC Series. The series was open to any vehicles of BMC
lineage with a first production date prior to 1973. The object was to
encourage the older English sports and Saloon cars, to keep on racing with a
strong emphasis on cars running full bodywork and trim. No engine
transplants from different makes or models were allowed, and bodywork had to
remain as original. There were a few exceptions, which allowed cars with
proven race history to be allowed to compete in the form they were raced in
during their era. When I first started racing in this class the front
runners were a mixture of MGB’s, Mini Coopers, TR2&3’s, MG Midget, MG ZA
Magnet, and a Wolsley 1500 which had been raced in the 1960’s with a MGB
engine fitted with a Derrington cross flow alloy head. Most cars were driven
to the racetrack, and then driven home again after a weekends racing. The
only V8’s were a few standard Jags and MGBGT.
After several years racing the BGT in the Standard and then Cat2 modified
classes both within the series and also in open class racing, I reached a
point where I could not get the car to go any faster without spending a
massive amount of money. (Money I did not have!) I was looking for a new
challenge and comparing laps times to the saloon classes, I found that my MG
would have been a lot further up the field if it was a saloon. By now I knew
most of the competitors in the BMC class and a couple of them told me that
they had previously owned and raced a Marina Coupe. One had owned one in
England and the other had actually owned a “Rally” version. Leyland brought
3 out to NZ in 1973 to compete in the Heatway sponsored Rally of New
Zealand. In fact Jim Richards had driven one in a few rallies around the
same time he was winning the NZ Saloon Championship in a Mustang. The first
thing I was told about the Marina from they previous owner of the Rally
version, as that he did not like the way it handled, so he sold it after a
short time. One of the BMC Leyland factory drivers refused to drive the one
offered to him, and he went on to win the NZ Rally in a Mini Cooper S.
Trying to track down one of the 4 factory produced Coupes lead to a few dead
end sorties with one being rolled and broken up for parts, another having a
Rover V8 fitted and then being rolled and written off. The best I could do
was track down one that someone’s wife was using as a shopping basket, and
the close ratio gearbox out of another was fitted to our club Captain’s MGB.
The same gentleman that had owned the rally car, just happened to have
another Coupe that his family drove around the farm as a hack. So I
purchased it off him together with a copy of the original Leyland Special
Tuning manual that he had kept after selling the rally car.
So together with my father (who is a mechanic, panel beater, painter and
engine builder) we set about turning a stock standard road going 1973 Marina
1800 into a racecar. The engine would be left to last, as we had plenty of
spare MGB engines and heads with a few radical ideas to try out for extra
performance. We had a very limited budget and wanted to get the car on the
racetrack for under NZD5000 (USD 2,500) including purchase price.
Body
The first thing that had to go was the slime green paint. We stripped the
engine & gearbox out and repainted it ourselves in white. The body was
pretty straight and only a few minor rust areas required attention. I had
previously remembered the glare problems I had when I owned a white Hillman
Avenger that had a big flat white bonnet. It was perfectly angled to reflect
all light directly into one’s face, so the Marina bonnet was painted in
matte black. The front grill from the australian Marina was used as it
allowed more air into the inadequate radiator, and ducting was cut under the
front bumper to divert air directly into an oil cooler which was fitted in
the position where normally sat. We had to cut into the inner guard to make
an area to fit the 15-row oil cooler, which had been donated from a Cortina
turbo that had blown up. The battery complete with the original mounting
platform was relocated into the boot to transfer some weight over the rear
wheels. The edges of the guards were rolled to give clearance for wider
wheels and tires. A 2-inch steel box section beam was made to tie the two
front ends of the chassis rails together. It would stop the front of the car
twisting, provide a point for jacking the car up, as well as provide a bit
more protection in a frontal accident. A full roll cage was welded into the
car, which provided a lot of stiffness to the body as well as the necessary
protection for race or rally events. We added an additional cross brace
welded through to the gearbox tunnel on the advice of the manufacturer for
extra strength. The Marina front seats were replaced with race seats and
full harness belts installed to complete the interior.
Suspension
Rear- shock turrets were made as per the Special Tuning Manual (ST) to take
the shocks vertically thought the boot floor. The stroke happened to be
perfect for fitting gas shocks from an EA Ford Falcon. (Later replaced with
KYB fully adjustable) Rear springs were replaced with Marina Van springs
with the extra leaf removed to soften the ride up a bit, and were then reset
for the desired ride height. After ripping the differential control arm off
the chassis on a rough road circuit, we threw it away. (The factory control
arms seemed pretty useless, and the way they swung the axle resulted in
several breaking before we finally ripped the bracket off the chassis) We
fitted two anti tramp rods, which had come off a Ford Anglia instead. Due to
the restricted space under the diff and make up of the hand brake system,
there was no easy way fit a Panhard rod or Watts linkage. All rubber bushes
were replaced with Nolethane if available, as were the front. Rear brakes
were replaced with a complete set of 9 inch Ford Escort drums that even
matched with brake pipes and hand brake cable levers.
Front – As this was the first car we had tried to modify with torsion bar
front suspension, it proved to be a little more complicated to successfully
complete while keeping within the rules. Using the English lower suspension
knuckle on an Australian upright, we created a considerable amount of
negative camber. The front shock was then shimmed to decrease the camber to
a more respectable negative 2 degrees. A van anti-roll bar was fitted
together with van torsion bars, which were slightly heavier duty. A friend
of ours had purchased the last Spax telescopic shock conversion kit in NZ,
so we had a quick look at it before manufacturing our own heavier duty one
which could take a range of different shock absorbers. Initially we used a
set of second hand Mazda 626 gas shocks, which were later replaced with a
set of Koni shocks with adjustable compression and rebound rates. The front
brakes were another easy conversion with Marina 6 brake rotors and Austin
Princess 4 piston calipers. These cast iron calipers are quite heavy, but do
not suffer from the distortion that some alloy calipers can suffer from. We
had already tried them on the MGB with great success although, a few minor
modifications are required to convert them to a single break hose set up.
The caliper backing plates were removed and ducts made to bring in fresh air
to cool the calipers instead of the rotor.
Wheels
We tried several different combinations with 13x6 inch alloy wheels fitted
with 205/60 tires, 13x7 with 215/50, and later 14x6 with 195/60 when we
wanted to gear the car up for higher speed circuits. Due to the rules of the
crass requiring road tires only, we settled for the cheapest high
performance road tires we could get. (Hankook Z2000)
Transmission
When we originally got the car it was fitted with a 4 speed triumph box with
overdrive on 3rd and 4th. The box did not last very long when the horsepower
was increased and it chewed out the main input shaft. We tried a few
standard Marina boxes, but they had a habit of chewing out the syncros. In
the end we replaced the box with a MGB full syncro unit which included
clutch, slave cylinder, and flywheel. With the MG box, we have had no
problems at all, and it was matched to the standard Marina differential with
a single piece drive shaft. For a while we also tried an MGB overdrive
gearbox with the interlock removed giving 7 forward gears. This was a
cheaper way of getting a close ratio gearbox, but was later removed to keep
the car within the regulations.
Engine
Original engine was removed and a standard 1800 with twin 1 ¾ inch SU
carburetors used initially. We made a set of extractors up and later
replaced them with a set of Moss MGB special tuning extractors. The SU’s
were hard to tune properly once we started to modify the engine, as we found
it difficult to locate a range of needles. They were replaced with a single
45DCOE Weber. Instead of using an MGB or Marina head, we used a Morris
Oxford 1600 head. The head is actually a few mm thicker with a smaller
combustion chamber. This allowed us to change to a more hemispherical
combustion chamber rather than sticking to the Westlake design. (And
redesign the ports while we were at it.) The standard valves were replaced
with larger Chevy racing valves cut down to size, and a race cam fitted. The
engine was over-bored to 1950cc, which required hand made head gaskets. To
increase the cooling the radiator was replaced with one from a Nissan
utility fitted with a Ford Telstar electric fan. The rest of the engine was
left pretty much standard with the only modifications being to the oil
galleries, pump, and water ways to improve flow. We changed valve springs
but left the rest of the rocker gear standard. This left a free revving
engine to 6800rpm with just on 105 bhp at the wheels, about twice the power
the standard road car had at the flywheel.
On track Performance
The immediate acceleration advantage over the MGB was obvious, particularly
off the start line. The car weighed in at just on 900 kg, which was about
150kg lighter than an MGB. This made it very easy to launch off the start
line and many cars were to be passed in the first few hundred metres of a
race. (At least until they got up to speed) Once up to speed the car became
a bit of a brick at around 100-mph, and struggled to hit between 110 - 120
top speed. I fitted a front spoiler from a later model Marina, which helped
stop the front lifting with the air going underneath and directed more air
into the radiator. When the car was run on our local racetrack in standard
trim it lapped the 3.2km circuit in around 1 minute 35 seconds. After the
modifications were made and a bit of tuning the suspension, the fastest time
came down to 1 minute 19 seconds, and I could comfortably circulate all day
in the low 1.20’s. The car still tended to nosedive quite heavily under
braking, and was quite averse to turning into the corners. I found that the
modified brakes would make it stand on the nose and the back would become
extremely light. The standard Escort drum brakes on the rear actually worked
out to be a perfect match with the front, and would very rarely lock up
before the front. The car would switch quite smoothly from under-steer to
over-steer as the weight transfer came on through the apex of the corner.
With the torsion bar front suspension all four wheels would remain on the
track most of the time. It did lift the inside front wheel in the air when a
bump was hit. Even at the high-speed sweeper of Pukekohe Park Raceway,
which was taken at about 100 mph, it would lift and I would have to steer
the car around the corner using the accelerator. It took many people by
surprise when I passed them around the outside on the fastest corner. Half
the time I was on the outside still trying to get the car to turn in!) It
was really under braking where there were significant gains. I found that I
could just about out brake all the other cars in the class, and still had
the foot flat to the floor on the accelerator well after the Jags were on
the brakes. What I lacked in straight-line speed was partially made up for
under braking and cornering. While the car was not the fastest in the class
by a long shot, it proved to very reliable. One engine lasted for about 7
years before it needed are rebuild. As the race series lasted the full
season, it was consistently finishing that lead to winning in 2000. I think
I have not been outside the top 5 in several years. |
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