THE LOLA T710
All pictures copyright Lola Heritage unless otherwise stated.
The T710 at Goodwood.
On two occasions in the past Lola had been involved in building cars for other manufacturers, the T130/T180 for Honda and the T370/T371 for the Hill Formula 1 team*. The third occasion would be with the T710 which was commissioned by General Motors to compete in the GTP class of the 1984 IMSA series in order to test their V8 and V6 engines against the formidable competition provided by Jaguar, Porsche, Nissan, and Mazda.
Unusually comprehensive technical details about the construction of the T710 and its 3.4 litre turbocharged V6 Chevrolet engine can be viewed in the Chevrolet publicity brochure which can be downloaded in zip format HERE.
T710 HU1, run by Hendrick Motorsport and driven by South African Sarel van der Merwe and England's David Hobbs, made its debut at Road America in August 1985 where it qualified 11th but retired with engine problems. The next race, the 500kms of Watkins Glen saw Hobbs and Vern Schuppan 7th on the grid but out of the race with gearbox failure. The two remaining races, the Columbus 5000kms and the 3 Hours of Daytona resulted in two more retirements but pole position at Daytona two seconds under the lap record saw there was nothing wrong with either the car or its engine.
The 1986 season saw the T710 used for the opening four races before being replaced with the new T86/10 and the design took another pole position at the Miami 3 Hours and then had its finest moment when it won the 500kms Road Atlanta race.
*Eric Broadley was of course involved in the early development of the Ford GT40 which took the Mk6 as it's starting point but Eric was effectively freelancing for Ford so Lola wasn't involved in the design/construction of the new car.
Year(s) of Construction: 1984
Total Built: 1
T710 SIGNIFICANT RACE WINS
|Miami - Löwenbräu Grand Prix of Miami
|Sarel van der Merwe
|Round 2 of the IMSA Championship (Qualifying Race)
|Road Atlanta - 500Km Atlanta Journal / Constitution Camel Grand Prix
|Sarel van der Merwe
|Round 4 of the IMSA Championship
This article originally appeared in Autosport magazine (29th March 1984).
Corvette for Le MansQUENTIN SPURRING describes the latest Chevrolet-powered Lola sports car project.
The brand-new Corvette GTP is the first purpose-built competition design to bear a Chevrolet proprietary name for 20 years. And it will carry that name not only to the home public in the USA, but also, if all goes to plan, to the crowds gathering at the very spiritual centre of sportscar racing— at Le Mans itself.
Designed and built by Lola Cars, to comply with both FIA Group C1 and IMSA GTP regulations, the Corvette GTP (or Lola T-710) features an advanced monocoque chassis with big twin ground-effect air tunnels. The power unit is a single-turbo, twin-plug Chevrolet V6 engine, producing about 700bhp.
Now being tested in England, the Corvette GTP will be racing in the IMSA GT series in the USA by mid-season, in the hands of a top privateer racing team If existing plans for the new car come to fruition, it will also appear in the classic Le Mans 24 Hours, although not until 1985 at the earliest.
The competitiveness of the Corvette GTP in future World Endurance Championship events depends on the new rules governing engine types and vehicle weights, which are currently being worked out by a special FISA Working Group. However, the early indications are that this could be a very useful package, with sufficient power and downforce to spare. Porsche and Lancia will be watching the Corvette GTP project closely.
It is cast in stone, and has been since 1927, that General Motors Corporation does not participate officially in motor sports. There have only ever been two exceptions to this. The first came in 1957, when Chevrolet's Zora Arkus-Duntov constructed the Corvette SS, a spaceframe sports-racing car entered by the factory, that appeared only in the Sebring 12 Hours. The second was the Corvette Grand Sports, a lightweight version of the Stingray, designed for homologation by Chevrolet for FIA GT racing. In the event, only five were ever built, competing in private hands in 1963-64. It should be stressed that the new Corvette GTP is not a third exception to the rule. Its competition programme will be entirely independent, with Lola Cars remaining closely involved with the project as constructors. There will be no financial backing from the factory, even though the project has been initiated with the full blessing of Chevrolet.
Lola Cars designed and built the chassis, but the other elements bear direct Chevrolet identity. The bodywork was styled by personnel from corporate design staff at the General Motors Technical Center in Warren, Michigan, its nose shaped to resemble that of the latest Corvette road car. The turbo Chevrolet V6 is being race developed in Salinas, California, by Ryan Falconer.
When its initial test programmes are completed, arrangements will be made with a privateer racing team, whose identity has not yet been decided, to campaign the car. This independent team will embark on a full race and development schedule with this and evolution chassis, to include early participation in the Le Mans 24 Hours as a realistic target. The project is expected to be racing in mid-season 1984, venturing away from the IMSA GT series in America to compete in France in 1986, if not in 1985.
For many years, the Chevrolet V8 power units have served General Motors well. In competition — always in privately entered cars — it has consistently powered winners in Formula 5000 single-seater racing and in a wide variety of sports-racing and off-road categories. In its various forms, it continues to succeed in NASCAR stock-car and Trans-Am touring car events.
But General Motors as a corporation is evolving away from the flagship V8, and towards new-generation V6 engines. The 90deg and 60deg Chevrolet six-cylinder engines are options in five of the range of eight Chevrolet road car basic models — In the Citation, Caprice/Impala, Celebrity, Camaro and Monte-carlo. They are noticeably absent in the latest Corvette, which is currently offered only with the charismatic 5.7-litre V8 powerplant. The US buyer is a notorious reactionary, suspicious even now of any manufacturer trying to sell him a downsize engine, but eventually the V6 engined Corvette will have to come. In this sense, then, the V6s — although offered in 229cid (3.8-litre) and 262cid (4.3-litre) forms, and very potent power units — do have an image problem. Hence, Chevrolet smiles on the application of a V6 in a thoroughbred sports-racing car, especially one such that displays for all to see the Corvette name tag.
Chevrolet is also interested in all means to put the new-generation engine under stress that will result in useful development and is therefore strongly supportive of this launch of this six-cylinder on a substantial competitions career. The re-emerging sports car racing arena is judged to be the ideal proving ground, in which to exploit increasing development and promotional opportunities. So, the Corvette GTP will provide for the V6, which is an integral part of Chevrolet marketing strategy in the foreseeable future, with a basis for both engine development and product promotion.
The progression thus far of this fascinating project owes much to the perseverance of Ryan Falconer, who is one of countless US engineers preparing Chevrolet engines for competition use. The cylinder capacity of the engine in the Corvette GTP coincides with the maximum allowed for stockblocks under Indianapolis 500 regulations, Falconer having first put this version of the V6 into a race car — Lindsey Hopkins's Lightning driven by Hurley Haywood — at Indy four years ago. But the Indycar project was cut short when the Hopkins team ceased operations.
Meanwhile, CART rules governing allowable turbo boost pressures penalised stockblock engines, and Falconer sought a fresh market in sports car racing. He tried in vain to convince Lola Cars of the potential of his V6 turbo as the 'standard' power unit of the Lola T600 sports car, but Broadley and his US agent, Carl Haas, adopted a cautious approach, and most of the GTP versions of this design were sold with the faithful Chevrolet V8. So, Falconer turned to a private team, Ted Field's Interscope Racing, and one of his twin-turbo V6 race engines was fitted to Danny the Ongais T600 for the 1982 IMSA series finale at Daytona.
Ongais was leading the race when the car was retired, and prospects for the next IMSA season looked good, even though IMSA banned the twin-turbo installation for the 1983 series. At Daytona and Miami, the Interscope team was equipped with a single-turbo V6 engined T600 and showed well, but then Falconer lost another team from under him when Interscope was suddenly disbanded. With the T600 series nearing the end of its production run, Falconer again approached Lola Cars with a view to taking the development of a single-turbo sports car engine onto the racetrack on a regular basis, and this time he was successful. Ultimately, the interests of Falconer and Broadley were consistent with Chevrolet's short- and long-term motor sports objectives, and a programme of mutual interest was launched. Chevrolet then produced a prototype body, which was fitted to an ex-Interscope T-600 chassis and shown to the public for the first time during Grand Prix week in Detroit in June, 1983.
At the time, this mock-up car was eclipsed by the announcement by the Ford Motor Company of a similar but completed race car project, the Ford Mustang GTP, which was racing (and winning) 10 weeks later and has since been a useful promotional tool for Ford which is actively involved in the project. While the Mustang GTP was winning its debut race in August, the mock-up Corvette GTP was shipped across the Atlantic to Lola Cars in Huntingdon, and final design and construction of the first pukka race car began in earnest.
The first prototype was completed in late February, and tested at Goodwood in early March by Jonathan Palmer. The shakedown was interrupted by the inevitable problem found in brand-new turbocharged race cars — overheating — but Palmer had time to be impressed by the handling and downforce, and was delighted with the throttle response.
The car has since been driven at Silverstone by Stefan Johansson, but principals in the project have not confirmed the schedule for the next test programmes. It is likely that more chassis testing will be undertaken in England before the car is sent to the USA for further tests. Neither is it yet decided which team will be participating in the project, the only firm decision in this regard being that Lola Cars will not itself field a factory IMSA operation. The probable choice will be a US based team with sports car racing experience, and several have already expressed an interest.
We shall see during the second half of the current IMSA season and, hopefully, at Le Mans next year.
The Broadley-designed chassis
The basis of the Lola Corvette GTP is a completely new monocoque designed by Eric Broadley and his team, specifically for this engine application. The monocoque is made from aluminium honeycomb material and features the mandatory Group C Prototype flat-bottom area (80cms by 100cms). The 120-litre tank is centrally located, between the fire wall at the back of the cockpit and the engine itself. The monocoque extends rearwards to the back of the fuel tank installation, where it matches up to the engine whose front plate is bolted directly to the chassis, in this way the engine, as in most Chevrolet racing applications, does contribute to the torsional rigidity of the car but there are also substantial A-frames to carry its weight extending right back to the big rear crossmember which carries the shock absorbers.
The rear suspension employs a straight-forward wishbone layout with outboard coil spring/damper units mounted direct to the cast uprights. The T710 features advanced pushrod front suspension with the absorber units mounted vertically, close together in very centre of the chassis and the anti-roil bar blades working directly off the rocker arm. Both front and rear anti-roll bars are adjustable from the cockpit. The brakes – 13ins diameter AP ventilated discs with long-distance calipers operate within the wheels.
The transmission is the commonly used Hewland VG-series transaxle with purpose designed bellhousing that allows the turbo installation to be mounted low in the engine bay. The exhaust pipe exits into the right-side air tunnel beneath.
There are two very large air intakes in the side of the body. The upper half of the left-side ducting feeds cooling air to the turbo intercooler and the lower half of the oil cooler, venting into the engine bay. The right-side ducting feeds the single large capacity water radiator.
Lola Cars has been able to retain the basic Chevrolet styling concept although the two air intakes are much larger than originally drawn so as to get as much air as possible into the turbo engine cooling systems. The bodywork itself is made from a carbon reinforced Kevlar weave and its design results from full-scale wind-tunnel tests. at the huge Warren facility, and from quarter-scale tests at Imperial College, London. The air tunnels are formed from a big, single-piece underwing made from pre-impregnated carbon and Kevlar.
In establishing its family resemblance to the Corvette, the nose section has a slightly convex rather than a flat or concave surface, and there is some air spillage but nevertheless the Lola team is satisfied with the front-end downforce, and careful research, balancing the deep air tunnels and the wide rear wing, has produced extremely satisfactory aerodynamic results. In fact, says Broadley, despite its shorter air tunnels the T710 can tuned to produce no less than twice the overall downforce available from its predecessor the T600, and is also showing itself to be capable of a low drag factor when setup for sheer speed. The rear wing itself, is also made from pre-impregnated carbon material, very light in weight, while its double support struts are of aluminium honeycomb with a carbon skin.
The vertical sides of the air tunnels extend to the very rear of the car, and the T710 is 1.5ins longer overall than the T600 at 188ins (477.5cms). The width is 79ins (200.7cms) and height 41ins (104cms), these dimensions about the same as on the T600, The wheelbase is also the same at 106.5ins (270.5cms), the front track is 63ins (160cms) and the rear track is 61cms (155cms). The vehicle weight will be on the Group C Prototype minimum of 850kgs and the Corvette GTP will be ballasted to comply with the 900kgs weight required by IMSA for cars with this type and size of engine. The BBS road wheels are 16ins. Diameter, 11 ins wide at the front and 14ins wide at the rear. Goodyear tyres are used.
The Corvette's engine
From the standpoint of endurance racing people seeking a wide variety of engine manufacturers perhaps the most significant part Of the Corvette GTP package is, indeed, its engine. The power unit is the 90deg Chevrolet V6, which is basically a shortened version of the small-block VB, a pushrod design with only two valves per cylinder.
The cylinder capacity of this Ryan Falconer developed unit is 209cid (3425cc) and the engine features the proprietary heavy duty cast-iron block with all-aluminium cylinder heads. it is aspirated by a single Warner Ishi turbocharger of the type used extensively in Indycar racing.
The engine has Bosch ignition and fuel injection and, with the Ishi running on a relatively low boost pressure of 70ins (1.3 bar it will yield about 700 BHP at 8500rpm. Initially, the likelihood is that it will be raced with about 650BHP on tap, but ultimately Falconer hopes to be able to give his drivers up to 720BHP on race days.
Jonathan Palmer testing the T710 at Goodwood.