The forgotten F1 car that could have been champion

People tend to remember the most successful Formula 1 cars - or the machines that were surprising or unmitigated disasters.

There are plenty that sit between those two categories and a small handful only missed out on winning championships by the smallest of margins. The 2005 McLaren MP4-20 raced by Kimi Raikkonen and Juan Pablo Montoya is probably the best-known recent example, but a less obvious car could have been a title winner 50 years ago.

The Brabham BT33 was not revolutionary in the way that the Lotus 72, which did win both the drivers' and constructors' championships in 1970, was. It was a typical car of the Jack Brabham/Ron Tauranac combination - a pragmatic and relatively conventional car executed well. It was greater than the sum of its parts.

The BT33 was the first monocoque F1 Brabham - the team had stuck to spaceframe construction for longer than most after Colin Chapman had shown the way with the 1962 Lotus 25 - but Motor Racing Developments (as the parent company was called) did have experience of monocoques from the 1968 BT25 Indycar.

After taking title doubles in 1966 and 1967 with the dependable BT19/20/24 series, Brabham had suffered a troubled 1968 as the new Repco engine - with double overhead camshafts and four valves per cylinder - proved unreliable and unable to match Cosworth's game-changing DFV.

A switch to the DFV engine, however, proved that Brabham was still capable of producing competitive F1 cars. The BT26A, in the hands of both Brabham and rising star Jacky Ickx (below right), was the only car to break the Matra MS80 and Lotus 49B stranglehold on pole positions in 1969. Ickx also won twice on his way to second in the standings.

PLUS: Jacky Ickx's 10 greatest races

Ickx left for Ferrari for 1970, but Brabham had hoped to lure Jochen Rindt back from Lotus. The two had enjoyed working together in 1968 and Rindt had faith in Brabham's engineering. In the end, Chapman managed to persuade Rindt to stay and so, just as in 1966 when lead driver Dan Gurney had left, Jack Brabham decided to delay retirement once more. He was 43 when the 1970 season began.

"One of my reasons for wanting to go on driving for another year was that we had the new monocoque car and I was pretty confident it would be good," wrote Brabham about the BT33 in his autobiography When the Flag Drops. "I started the year with more confidence than I'd had since 1966."

Tauranac had worked hard to ensure the car was easily adjustable, allowing easy set-up changes; its potential was certainly easier to access than the more knife-edge early Lotus 72

Brabham had lost Gulf sponsorship prior to the season, but a deal with Auto Motor und Sport magazine meant a second BT33 was prepared for Rolf Stommelen to drive alongside Brabham.

"Perhaps the most surprising thing about the new BT33 is that it was designed as long ago as February/March 1969 and was in fact intended for the 1969 season," reported Autosport before the 1970 campaign began. "The reason for this is that, when the Repco engine was abandoned and the switch to Ford made, Jack Brabham was not certain that the existing BT26 chassis would mate happily with the Cosworth V8, so as an insurance the monocoque BT33 was designed.

"However, the BT26 with the Ford engine was perhaps one of the fastest on the tracks so it was not necessary to proceed with the BT33, although the chassis was completed in mid-season and pushed into a corner."

This inauspicious start was made worse by a rule change for 1970 that mandated rubber bag fuel tanks. Autosport argued that the BT33 had been designed without these in mind; once added they reduced the original car's fuel capacity and subsequent cars (three BT33s were built) had wider cockpits to compensate. The BT33 was not a svelte machine, particularly when compared to the Lotus 72, which had the radiators mounted on the side instead of in the nose.

But in Mark Hughes's book F1 Retro: 1970, published in 2013, designer Tauranac gave a different account. He argued that the downforce of cars of the era meant a spaceframe chassis could easily be made stiff enough and indicated that it was the rule change that forced the monocoque switch.

"The reason I had favoured spaceframe was aerodynamic," he said. "With a monocoque you had to run the aluminium sidepods almost parallel to the front wheels to have enough space for the tanks, whereas a spaceframe allowed you to do glassfibre sidepods that you could shape so they swung in and have them narrow so that you got the nice elliptical shape that the airflow prefers."

One BT33 novelty was inboard suspension. Autosport suggested that "there are no terribly technical reasons for doing this except that the adoption of 13-inch front wheels makes the use of outboard springs difficult due to lack of height", adding: "Certainly aerodynamics played no great part in the decision."

Again, Tauranac's account suggests Autosport got that one wrong. The BT33 had already been in a windtunnel in an effort to reduce drag.

Pretty much every other element was regarded as conventional - proven would perhaps be a better word - and Autosport described the rear suspension as "virtually the same as that of the BT26".

Autosport concluded that "the BT33 is by no means the last word from Brabham in 1970. One can look for a new Brabham that will probably be appreciably smaller than the BT33 - an exciting possibility."

That was probably a little harsh on the BT33, given that Tauranac had also worked hard to ensure the car was easily adjustable, allowing easy set-up changes for the prevailing circuit and conditions. Its potential was certainly easier to access than the more knife-edge early Lotus 72.

Testing went well too - and then Brabham sensationally won the season-opening South African Grand Prix at Kyalami. He did so by catching and passing reigning world champion Jackie Stewart after contact with Rindt at the start and falling to sixth. It was his first world championship race victory for more than two years.

PLUS: Jack Brabham's 10 greatest drives

Brabham was not regarded as a qualifying master, but took the 13th (and final) pole of his world championship career next time out at Jarama. He made a poor start, which meant he was behind Denny Hulme when the McLaren driver had a slide at the spot Ickx and Jackie Oliver had suffered a fiery shunt on the first lap. Brabham reacted and spun, then spun again shortly afterwards trying to make up ground.

This was a 44-year-old veteran in an orthodox machine hounding a driver regarded by many as the fastest in F1, driving a car that would still be winning GPs four years later

After being stuck behind Jean-Pierre Beltoise's Matra, Brabham put on a charge that took him to the back of leader Stewart's March. Another win looked on until the engine failed.

The Monaco GP became infamous. Once Stewart's March had retired, Brabham led until the final corner, when he slid off into the straw bales lapping Piers Courage's De Tomaso. A charging Rindt shot by to win, with Brabham recovering to second.

It was a blow, but Brabham now led the points race and could have won the first three rounds. With Lotus still trying to get the 72 working (Rindt had switched back to the 49C for Monaco), Stewart stuck with the tricky March 701 and Ferrari struggling to get its new 312B to finish races, Brabham had an opportunity.

A lack of straightline speed was a hindrance at the Belgian GP at Spa, round four of the campaign. Brabham managed to rise as high as third before the clutch fell apart, but he still led Stewart in the points race.

The BT33 wasn't competitive at Zandvoort for the Dutch GP (none of the Goodyear runners were), but the more crucial development was that Lotus now had the modified 72 working. Rindt dominated the race and moved to the top of the table, tied with Stewart, who had finished second.

Another sluggish getaway in the French GP restricted Brabham to third at Clermont-Ferrand as Rindt won again. It looked as though Brabham, now eight points behind Rindt, had missed his chance, but round seven at Brands Hatch would suggest otherwise.

Brabham had set the pace at the Race of Champions at the Kent venue four months earlier, only being denied by an ignition problem in the last three laps. He carried that form into the British GP, the BT33 now with inboard rear brakes, matching Rindt's pole time for a place on the front row.

Although Brabham led initially, it was Ickx's Ferrari that jumped into the lead with a forceful move on the inside at Druids. Ickx pulled away while Brabham and Rindt battled, but a key moment came when the Ferrari's differential failed as Ickx entered Paddock Hill Bend.

At the same moment, Rindt dived up the inside of Brabham. They were wheel-to-wheel as they caught the retiring Ferrari and the Lotus made it by ahead, jumping from third to first.

For the next 60 laps the gap between Rindt and Brabham would not grow more than 1.5s and was usually less than 1s, the 72 perhaps a little faster in a straight line. This was a 44-year-old veteran in an orthodox machine hounding a driver regarded by many as the fastest in F1, driving a car that would still be winning GPs four years later.

Finally, on lap 69 of 80, Brabham took his chance when Rindt missed a gear. He quickly pulled away and Brabham was 13.3s ahead of Rindt with a lap to go. Then the BT33 spluttered as it ran out of fuel.

Brabham, who later suggested that the cause was a mechanic leaving the mixture setting too rich, crawled over the line to finish second as Rindt took his third win in a row. It was poor reward for one of Brabham's greatest drives.

"Of all the disappointments in my racing career, maybe that one hurt more than most," Brabham later wrote.

With six rounds to go, Brabham was still second in the standings, 11 points behind Rindt and 21 head of Ickx in 12th. Given the tragedy that would later befall Rindt and that Ickx would finish five points behind F1's only posthumous world champion, Brabham could still have taken the title. But now the team really lost momentum.

Many problems in Germany culminated in a retirement with an oil leak. In Austria, Brabham got up to fifth before a stone punctured his radiator, while overheating and then a crash on oil ended a promising Italian GP.

"I should have won the world championship in 1970" Jack Brabham

After Rindt's death in practice at Monza, Brabham left Italy tied for second in the points with Stewart, but there were no points in Canada or the United States GP. He had now gone five races without scoring.

"When we reached home we decided it was time to find out exactly why our car was so slow," said Brabham in When the Flag Drops. "Eventually we found that, after Brands Hatch, an oil line had been changed from the breathing system of the engine to the oil tank.

"This had created tremendous back pressure in the engine and it had been getting too much oil in the sump, and wasn't scavenging properly."

Problem fixed, Brabham went to Mexico for his final GP. He qualified fourth, second of the DFV-engined runners as Ferrari flexed its flat-12 muscle. Despite another poor first lap, Brabham climbed to third when Stewart's rapid new Tyrrell retired, only to suffer engine failure with just 13 laps to go.

Stommelen also had a troubled season, though he did take third at the Austrian GP and Brabham finished fourth in the constructors' table, behind Lotus, Ferrari and March.

Brabham running on Goodyears, as opposed to the Firestones used by Ferrari and Lotus (and Dunlops for Stewart), had undoubtedly played a part in the BT33's pace on hotter days, but Matra and McLaren had been on Goodyear rubber too and neither won a race.

"I should have won the world championship in 1970," argued Brabham years later.

The fact he shared fifth spot with Stewart on 25 points, 20 behind champion Rindt at a time when a win garnered just nine points, superficially suggests that is fanciful. But had it not been for the mishaps or the breathing system problem, it is possible that Brabham would have overhauled Rindt's tally and taken his fourth crown before retiring from F1.

Although the 1971 BT34 would win two non-championship F1 races, the Brabham team would have to wait until new ownership and Gordon Murray's BT44 in 1974 before it again reached the top step of a world championship podium.

There are plenty of 'ifs' in motorsport history, but the BT33 deserves to be remembered as a car that got far closer to taking F1's biggest prize than it gets credit for.