Tyrrell P34 - Ford Cosworth DFV

This car has been meticulously built to the original drawings of Tyrrell, and is a perfect continuation of the original cars that became iconic in the hands of Jody Scheckter, Ronnie Petersen and Patrick Depailler during 1976. Built under Licence from Tyrrell, Chassis 10 is offered today having undertaken a shakedown test from build, complete with period correct Richardson built long stroke DFV, this car is an exciting opportunity to acquire one of the most iconic F1 designs of all time, and a car that can be driven, raced at the world's premier motorsport events, or just admired....

Offered for sale complete with current FIA HTP, spare wheels, and running equipment please call for more details.

The following article is from Magneto Magazine and explains the story behind the car and the build process...
Well, when a noted design engineer was informed of the plan for a brace of Tyrrell P34 ‘continuations’ – why build one when you can build two – his original thought was: “Good luck with that.” It was a view underpinned by a half-century of knowledge and several months’ direct personal experience. John Gentry had joined Tyrrell in mid-1977 and watched with interest – and a cup of coffee – as mechanics laboured to prepare these complex cars for their next Grand Prix. He was semi-detached from the process having been drafted to draught details of 008 – the P34’s replacement – by Maurice Phillippe, the man scheduled to replace Derek Gardner, the P34’s designer. The atmosphere was taut.
“We weren’t allowed into the drawing office – especially Maurice,” says Gentry. “We were working from no more than a double garage with a couple of drawing boards in it. But I knew [chief mechanic] Roger Hill, and would often speak with him about the P34 and its difficulties; he was forever taking apart its front wheel bearings – tiny little things – and grinding them to try to generate a bit more pre-load, to no avail. Those front brakes were always an issue. “I’d been sceptical about the P34 – interested in its concept but glad that somebody else was doing it. When it did well immediately in 1976, we were all thinking: ‘Christ! We’ve got to build one now.’ By 1977, however, I think even Tyrrell was pleased to see it go. That front end brought a lot of complication and problems.”
That’s why Alistair Bennett, director of
Warrington-based CGA Race Engineering, gulped when US client Jonathan Holtzman – who had been thwarted in all his bids to buy
an original – posed that leading question. “We were driving somewhere when he said it off-handedly,” says Bennett. “I replied that itwas possible given the resources we have today, but that the difficulty always is to get
such cars accepted. I didn’t realise how deeply the seed had been planted. A month later, he came back to me: ‘How well do you know the
Tyrrell family?’ Oh Jeez, here we go!” Hello, is that Mr Tyrrell?
“We had never considered such a thing,” admits Bob Tyrrell, son of late team founder Ken. “We thought long and hard – insisted that they
be known as continuations and have their own chassis numbers – but ultimately decided that it would be a shame if a six-wheeler never raced
again. It’s arguably the most famous Formula 1 car. That’s why we agreed to licence two more. “Dad was a straight-talker who kept a very
good secret. He was a bit of a showman, too, and he had the mechanics build wooden half-hoops so that the car’s outline looked normal. He then removed its cover from the back to the front. Slowly. The room fell
silent. I think the press thought we were having a laugh. To be honest, we didn’t know if it was going to work, either.”
That cheeky reveal was in September 1975, when only Gardner, a deep thinker inclined to fret, was sure that the concept would work. He
had conceived it as long ago as 1968, while working as a transmissions engineer for Harry Ferguson Research on the Lotus 56 Turbine
project. Its four-wheel-drive system failing to provide the anticipated stability at Indianapolis, he schemed in his own time a 4-2-0
arrangement, the rearward front axle of which would be driven as well as steer.

He fought shy of showing it to Colin Chapman, the high priest of racing-car design, and instead sent the proposal to team sponsor/lead Andy Granatelli. The silence from the usually OTT boss of STP was deafening. And discouraging. Not until seven years later would Gardner, desperate to break free from F1’s jostling ‘kit car’ pack, revive the idea, albeit in rear-wheel-drive form. He was well established by then, having been
given his big opportunity when big-business politics had forced Tyrrell to become a constructor in 1970. Ken considered the unheralded Gardner to be a safe pair of hands – they had worked together on Matra’s 4WD F1 project of 1969 – and his safety-minded number one Jackie Stewart approved his choice for that same reason. Which is why the
Scot almost choked on a drink when Gardner outlined his radical vision of the team’s future during the return flight from the 1975 South
African Grand Prix, as won by local hero Jody Scheckter in Gardner’s conventional 007.

The P34’s fundamental tenet was the reduction of aerodynamic lift by placing four small front wheels in the lee of a bluff nose. Its being balanced by a smaller rear wing creating less drag was reckoned to be of benefit to (gathering) straight-line speed even though
fat ‘dragster’ rear slicks delineated overall frontal area still; Gardner calculated its worth to be at least 40bhp. Other mooted gains were a contact patch greater by 60 percent and an increased swept area; that’s turn-in and braking sorted. In theory.

When Scheckter brought his ‘five-wheeler’ to a smooth if “slightly spongy” halt in the pits at Anderstorp, the eager Gardner perched on a sidepod as mechanics circled protectively if inattentively. There came not a flicker until the driver – “It’s got some understeer” – cracked and pointed to the (apparently not so immediately) obvious gap where the front-front-left wheel ought to have been.
The deadpan South African grabbed pole for the 1976 Swedish Grand Prix the next day. And the day after that, he and team-mate Patrick Depailler scored a 12-wheeled 1-2. The only person laughing in the F1 paddock now was Ken Tyrrell.
Jonathan Holtzman, a successful real-estate developer from Michigan and a former Formula Junior team-mate of 1996 IndyCar champion Jimmy Vasser, wanted to capture that moment by building P34s precisely to the specification used at Anderstorp. And so the search for information began.
“We cast the net widely; photos, sketches, documents,” says Bennett. The primary source was approximately 230 period design drawings – a trove sadly denied several Tyrrells in the aftermath of the team’s 1997-’98 takeover by British American Racing. “Some were hand-drawn by Derek himself; very cool. And probably about 75 percent were useful. Some had been superseded. For example, there were two versions of a front upright, one of which had a line through it: ‘No!’”

Bennett, son of long-time team owner/good guy Colin, has petrol in his veins: “I was travelling with our Formula 3000 team at weekends when in the late 1980s these things called laptops came along to irritate the life out of Dad,” he says. “I was doing computing at school and so could help connect the dots of early data-logging. I wanted to go racing immediately after leaving school, but the Gulf War recession hit us hard; Dad [and Alistair’s younger brother Jonathan] went to the States to work for a collector of classic Porsches, while I went to the University of Central Lancashire.”

Graduating in computer-aided engineering, Bennett “did a bit of automotive, a bit of aerospace” before the expansion of historic racing – its chronology and technology – allowed son and father to work together once more. “And here we are ten years later,” he says. “We are not a racing team that tries to do a bit of engineering; we are an engineering company that goes racing. I pinched that quote from Frank Williams. If you pay attention to the engineering input, you can generally get the competitive output you want.

“Even so, this was to be our first ground-up chassis drawing, and we are not arrogant enough to think that we were going to dot
all the i’s and cross all the t’s. To make it
blunder proof we hired John Gentry to go through the structural elements, double-checking everything we’d drawn.”
Gentry had spells at March, from 1970, Shadow and Fittipaldi in F1 before aligning with Tyrrell; he would go on to work for ATS, Alfa Romeo, Toleman Group Motorsport (alongside Rory Byrne) and March/Leyton House. He also has experience of GP bikes via Suzuki and Yamaha, plus BTCC with TWR Volvo, A1GP, GP2, WEC, Scandinavian TCR and Formula E. Between times he has been the FIA’s technical delegate for its Historic F1 Championship. His role in this project was as overseer to CGA’s CAD wizard Simon Harris and project leader/problem solver Bennett.
“They turned out an excellent solution,” he says. “But I think they were happy if someone experienced said: ‘Hang on, what about if we did it this way?’ The second monocoque in period tended to be different from the first; small changes that we liked to think would improve its structure and/or its ease of manufacture.”

Fellow historic racing specialist Hall & Hall helpfully arranged access to a disassembled original P34 – Richard Mille’s chassis 6 from 1977 – which CGA uploaded using a handheld laser and 3D-measuring machine. H&H would also help with carry-over from a Tyrrell 006 of 1972-’73; major rear suspension components, how the gearbox is specced, and more.
“In the embryonic phase it was critical to see how the car had been constructed and to note the physical differences between the 1976 and 1977 versions,” says Bennett. “We rapidly had the car more or less buttoned down digitally.” Harris, another Central Lancashire alumnus, converted 2D drawings into surface CAD for about 85 percent of the car. But the manufacture was a different matter.
“The tricky bit has been the engineering and construction of the chassis. The rear end is relatively easy. But much of the P34 ahead
of its rear bulkhead is bespoke. The front uprights are a case in point; half-upright/half-caliper, a strange arrangement, squeezed into a small space. Thankfully we had a drawing that married up with the CAD; it was still a load of machining, though.

“We had the tub’s outside dimensions, but that was only the beginning. We had to sift through the drawings and assemble them in CAD, and then look at what was drawn versus what actually works. Because these are continuations, we reserved the right to assess each component on its own merit. The rollover structure, for example, is well defined in FIA Appendix K these days. But that’s not what was drawn. Ours has the same geometry, sizes, height and position as the original, but the materials have been altered to reflect current practices.
“In terms of materials, however, Tyrrell was one of the better teams of that period. (We got the aluminium for the chassis from Boeing – only it has sheets big enough – and it checked that it would still have enough in stock before it’d sell to us.) After converting the old specs, there were a few anomalies but nothing ridiculous.
“The 1976 Autocourse annual said that one of the hiccups with the P34 was how difficult it was to build each chassis; dad took great pleasure in reading that out, as our first tub went six months behind schedule.
“The tub’s floor is bent around at its extreme edges, where the sidepods are, and turned into a triangular structure that goes back up into the driver’s cell. It’s one piece. You then have to construct the rest of the chassis through a ‘letter box’. Bending hard aluminium on-grain so that it doesn’t crack; baffles, side panels and other floor pieces are fitted at arm’s length without being able to see what you are doing. It’s a ship in a bottle. Blindfolded. I am so impressed that they were able to make it on a tight deadline, while running other cars, back in the day. We were teed up to have six people full time until the cars were finished. That’s probably similar to what they had at Tyrrell.

“The nose caused us a semi-panic attack,” says Bennett. “We had overall plan drawings, but nothing that pulled it all together. So we bought the biggest scale model we could find on the internet and did a 3D scan of it, in its kit form, that Simon then blew up to actual size. The scanner will go down to a micron or two, and so it looked like a ploughed field in some areas as raw data – but it was a big help. We found a generic brake-duct drawing that we could now link to a scan. The missing bit was a section of curve – an ‘eyebrow’ – that keeps the flow of air inside the ducts and dictates how it is split between the hoses. A beautiful detail.”
It’s fair to say these guys have gone to town; heart and soul, as well as nuts and bolts (plus a box of painstakingly collated ‘finishing bits’; some original gauges, a steering wheel – “We think” – and part of a gear linkage). Both cars, their builds – including a pre-paint/pre-anodised dummy run – overseen by Jonathan Bennett, will race using correct-spec Cosworth V8s, correct fuel pump in the right place, prepared by Geoff Richardson Engineering; DFV 1260 for chassis 9 and DFV 1261 for chassis 10.

“I’d challenge anybody to prove that any P34, apart perhaps from the one owned by Tamiya in Japan, has the actual engine it used in period,” says Bennett. “On the high-pressure crankshaft, DFVs were fairly fragile, and were in and out of different chassis like you wouldn’t believe.
“But what’s ‘original’. We’ve scanned an original car that’s been subject to maintenance, and you can see what bits are reworked/original/new; it’s strange how things creep over the years.”
Gentry is sanguine: “Outwardly these cars will be identical to the original”.
Extract from Magneto Magazine