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.