THE INSIDE STORY TO BRITAIN'S MOST FAMOUS COMPETITION DATSUN Z-CAR, "BIG SAM"
Old warriors never die, they say. In the case of the racing Datsun 240Z "Big Sam" that certainly seems to be true. Heís been doing battle for thirteen years now and he just gets faster and faster. Big Samís major claim to fame is victory in the 1974 BARC Modsports Championship but the story didnít start or finish there.
TKS 33 SA 695. To most people it means nothing, but to the initiated itís the Japanese registration number of a 1970 works Datsun 240Z rally car. Chassis number H530-00025 was one of the very first batch of works cars. They were built in Japan and shipped to England in late 1970, just in time for an assault on the RAC Rally. Five cars in all arrived, pristine in bright fire-engine red with matt black bonnets and front wing tops.
There was very little time before the RAC, so it was after only a couple of days testing on the rough army range at Bagshot that 695 made its debut in the capable hands of 1967 Monte winner Rauno Aaltonen. Aaltonen had spent some time earlier that year developing the car. He had enlisted the help of Tony Fall following the Monte and between them they had tested prototype cars and given many recommendations to the Datsun Competition Department, who in turn had done an excellent job of interpreting the recommendations into a revised specification.
The cars for the RAC were described by the works as "fairly standard", but as the model had only been launched a matter of weeks earlier at the Motor Show nobody knew what "standard" was. It turned out that the power output had been raised by a third to 200 bhp by the addition of three twin choke Mikuni-Solex carburettors (similar to Weber DCOE), a special camshaft and a fabricated big bore exhaust system terminating in twin megaphone pipes. The five speed box boasted closer than standard ratios, fifth being direct whereas the production box had a direct fourth and an overdrive top. The transmission was completed by a very low ratio (4.87:1) limited slip differential. Group Three regulations in those times allowed the use of fiberglass panels, so Datsun took full advantage by using the material for the bonnet, doors and tailgate. Perspex was employed for the side and rear windows. With the very low gearing and lightweight body the powerful six-cylinder engine provided impressive acceleration. The Healey theme was revived.
The RAC was not a fairytale event for the new cars, but bearing in mind the fact that it was their first outing it can hardly be considered a failure. The only weak link turned out to be the transmission which failed on each of the four entries (the fifth works car was used as a high-speed service car). The failures were probably due to the special differential coolers being removed because the weather was so cold! 695 broke a driveshaft on the first Clipstone stage, but Aaltonen thought he had only collected a puncture and drove to the end of the stage. It was here that the real problem was diagnosed, but by that time the rear brake pipes and cables had been torn out by the wildly revolving shaft. The crew removed the offending shaft and completed the next stage with front brakes only, after which the service crew cannibalized their Austin 1800 service car to obtain a spare shaft. Quite a few Datsun parts not only looked like BMC items but also actually fitted!
The brakes were repaired bit by bit during the Saturday night and by Sunday morning 695 was fully serviceable once more. It was late in the event, on the return from the Scottish loop, that the differential failed. But, with repairs effected at a nearby control, Aaltonen/Easter brought 695 home a creditable seventh - having set three fastest stage times on their way.
TKS 33 SA 695, in common with the other works cars was used on home events during 1971 and finally put out to grass at the end of that year. 696, chassis H530-00026, which was John Bloxhamís RAC car, went on to win the ë71 Welsh with Tony Fall at the wheel before being sold to Withers of Winsford. Edgar Herrmannís RAG car, 694, H530-00024 was sold to Rob Grant and Martin Birrane who converted it into a racer and campaigned it mainly in European Group Three races. 694 was taken down to South Africa for a major international at Kyalami and was written off. The team needed a new car and acquired 695, the ex-Aaltonen car, from the works. 695 was mildly modified and taken over to Portugal where, with backing from Cona Coffee, it took part in a couple of races. It was here apparently that Rob was puzzled as to why people kept sniggering at 695. Then the Clerk of the course suggested they should cover up the sponsorís name and explained the unfortunate meaning of "Cona" in Portuguese!
In the meantime one Spike Anderson, who was Ralph Broadís cylinder head man, left to start up on his own. This was early 1973 and money was tight so Spike sold the last of a long line of Healeys to put some cash into his business, Race Head Services. It wasnít long before Spike felt the need for something sporting again and investigated a brand new red 240Z in a local showroom. Spike was caught, hook, line and sinker and soon become the proud owner of FFA 196L, his first and last new car!
Being used to hot Healeys, including a small block Chevy V8 powered version, Spike was soon looking for more power. He re-worked the cylinder head, fitted triple Weber 40 DCOEís and a fabricated exhaust manifold. Suspension mods followed along with a special paint job. The Samuri was born. Clive Richardson of Motor Sport tested Spikeís 140 mph 240Z, published an article, and suddenly Spike found himself in the Z tuning business.
Having made his 240Z go and handle the way he wanted it, Spikeís next task was to try to find a way to stop it! He was soon rigging up AP ventilated disc brakes complete with the much more efficient four pot calipers. Before AP would sanction the conversion for sale to the public they insisted on a specially observed two-hour circuit test. Spike called in Hugo Tippet to do the driving and on completion of the test Hugo was heard to comment "if thatís a road car, what the hell would a racer be like?" This started Spike thinking and it wasnít long before he and his partner Bob Gathercole acquired TKS 33 SA 695 from Rob Grant. It was still very much a works rally car, and work started to build the ultimate Super Samuri, Big Sam.
The wings were flared sufficiently to cover 10" Minilites at the rear and 9" at the front. A deep front air dam was fabricated and a standard 240Z rear spoiler added; no spoilers were fitted to the rally cars. The bodywork was finished in the Samuri colours of Flame red with bonnet top and roofline profile in Rootes Tango metallic, all outlined in white.
On the mechanical side huge Can Am brakes were fitted at the front and the suspension was re-worked by Tivvy Shepton. The original works engine, gearbox and limited slip were retained for the time being.
The first race was scheduled to be at Silverstone early in 1974 but Big Sam didnít make it to the grid after blowing a cylinder head gasket in practice. While the car was trailed back to Spikeís to be repaired for Croft the next day, Big Samís place on the grid was taken by FFA 196L, Spikeís road car. It won its class driven by the unknown Win Percy who was to drive Big Sam for the rest of the season. Spike had built a road going Samuri for Win, who promptly beat him with it at a hillclimb! Hence the invitation to drive Big Sam.
At Croft Big Sam arrived with a new head gasket but was still virtually untried. On the first practice lap it stopped. Fuel starvation was diagnosed and various attempts made to effect a cure. Finally the problem was solved, but Win had to start from the back of the grid. By lap 2 Big Sam was second. Then the engine blew up in a most comprehensive fashion.
Upon examination it was found that the rear main bearing had broken up and caused the blow up. The team built a new engine with a much modified rear bearing from assorted bits. It produced around 220 bhp and lasted until mid season. By that time Big Sam was proving to be something of an irritation to the Porsche Carreras who, with a 400cc advantage, were having a real fight for the Championship. At Llandow there were three competitive Porsches and the race which resulted was a first class battle. Each lap Win brought Big Sam across the line with the three Porsches snapping at his heels. As the leading group came onto the main straight the extra power of the Porsches showed and, one by one, they would file past the Datsun only to be outbraked into the hairpin. This happened lap after lap until on lap thirteen of a fifteen lap race Big Sam crossed the line and threw a big end bolt. The mechanical carnage, which resulted, was such that a new engine was required.
The lessons of Llandow, namely the need for more power and more bottom end strength, were to be built into the new engine. A "one off" Gordon Allen crank was made, as Spike puts it "at a price I wonít even tell you!" Corello rods and a Trans Am cam from the American Z tuning specialists Brock were added along with new domed pistons giving an 11:1 compression ratio. The new engine was completed and at its first test it smoked. It was dismantled again and it was discovered that the gudgeon pin circlips had broken up allowing the gudgeon pins to float and scrape the bores. The teamís engineer, Barry Hudson, made up Teflon bungs, which were a push fit into the piston small end holes. These prevented the gudgeon pins from floating by taking the place of the circlips. It worked perfectly, but the bores were slightly scored and the engine always smoked a little. Samuri however, took great pleasure in informing their competitors that they were running "non-stick" pistons! The power output of this new engine was around 250 bhp and the super strong crank was good for 8000 rpm. Just what was needed to beat the Porsches.
The battle with the Carreras continued until oil on Bottom Bend at Brands Hatch caught out Big Sam and a heavy accident followed. Big Sam was banana shaped, his back broken. The teamís only chance of winning the Championship was to rebuild Big Sam with a new bodyshell. The price of a new shell was totally out of the question so Datsun UK was approached. Mike Greasley offered them a battered rally shell, which was lying around. It turned out to be Shekhar Methaís 1972 Safari and Scottish shell, which was in a fairly sorry state. The bare shell was taken to the Samuri workshop and the job started to straighten it up and fit the ex-Aaltonen mechanicals into it. Straightening proved to be quite a task; as Spike puts it "the front legs pointed in opposite directions and we never did get the screen to fit properly". Big Sam was running again in ten days in time for Castle Coombe where he arrived finished in primer with what has been described as "interesting" sign writing. Win brought the car home third.
The Championship was drawing to a conclusion and Porsche GB was somewhat worried. A senior Porsche official was overheard muttering something about "nailing that *@!*?* Datsun to the wall". The nail turned out to be a full house ex-works Carrera brought in for the number one Porsche driver Nick Faure. It was intended to give Porsche the Championship, instead it expired on lap three leaving Big Sam to cruise round to take the title by a single point. In all Win and Big Sam took four lap records on their way to winning the only national championship won by a 240Z outside Japan or the States.
In 1975 Big Sam was sold along with a host of works spares, largely the remains of TKS 33 SA 694, the first Grant/Birrane racer, to John Bradburn of Bradburn Bros. the Wolverhampton Datsun and classic car dealer. John spent some time re-preparing and lightening the car for the 1976 hillclimb season in which he competed successfully. Following that season Big Sam was stripped for a re-build and later in the year David Sutherland expressed an interest in buying the car. A deal was struck and Big Sam, now as a rolling shell, was sold. John retained the special crank, rods and cylinder head, along with most of the ex-694 spares. These spares have since been rebuilt into another racer, but Big Samís expensive internals remain unused at present.
Big Sam was modified and reconstructed using less exotic components by his new owner and John Rich of Fourways Engineering and, in 1980, Spike was able to re-acquire the car.
For 1981, The Year of the Disabled, hand controls were fitted for the car to be raced by Martin Sharpe who had been disabled following a motor cycle racing accident. Martin could not use his right leg so for driving he crossed his legs and used his left foot for the throttle and brake. Heel and toeing was impossible so a tandem hand throttle was rigged up to allow him to blip for down changes. Various methods of power assistance for the triple plate clutch were tried and finally a triple servo operated handgrip mounted on the gear lever was successful. Can Am brakes were now employed on all four corners which brought with it problems of oil surge. Even with a baffled sump all the oil would be thrown to the front, leaving nothing for the oil pump to pick up. After various ideas were put forward, discussed, and discarded they opted to simply overfill the sump by about half a gallon to ensure that the oil pump pick up would never be dry! It worked very successfully, but the lack of oil had damaged the engine and it was rebuilt as one of Spikeís "trick" 260 units (240Z crank, 280Z bore 2.6 litre short stroke). Big Sam and Martin Sharpe finished second in the BRSCC Championship being beaten by Mark Halesí Marcos. At the last race of the season the engine blew in a big way, the now standard crank couldnít take 8300 rpm! The block literally broke in two giving Big Sam his last award Silverstone "Blow-up of the Year"!
Big Sam is now in temporary retirement and is being restored. At the moment he is complete with the exception of still having no engine. But never fear, Big Sam will be back, "CAUSE OLD SAMURIS NEVER DIE....