Guide: Mirage M2
Background
For the 1968 World Sportscar Championship, the FIA unilaterally decided to impose a three-litre engine limit for Group 6 Prototypes. At a stroke, this made cars like the Ford Mk4, Ferrari P4, Mirage M1 and Chaparral 2F obsolete.
Speeds had risen to the point that the FIA felt they had no choice but to act.
Several manufacturers were deeply unhappy that the decision was made without any prior consultation. Famously, Enzo Ferrari was sufficiently peeved that he decided to play no part in the 1968 World Sportscar Championship.
In addition to the Group 6 Prototype category, manufacturers could contest the existing Group 4 class which had a five-litre engine limit but a production requirement of 50 vehicles.
The 4.7-litre Mk1 Ford GT40 was one of the few cars already homologated in Group 4. Realising that an extra 2000cc over the Group 6 Prototypes may prove a race-winning advantage on certain tracks, John Wyer’s Gulf-backed operation (which had acquired Ford Advanced Vehicles and the rights to the GT40 from the parent company in late 1966), decided to abandon the Mirage M1 programme and build a small batch of new Group 4 GT40s with all the latest bells and whistles.
However, this was only a temporary stay of execution for the old bruiser. As the GT40 was not expected to be particularly competitive by 1969, Wyer’s outfit began development of a new three-litre Group 6 Prototype: the Mirage M2.
The Mirage M1 had been a lightened and streamlined interpretation of the GT40 produced by John Wyer Automotive Engineering (JWAE) for 1967. It famously won the Spa 1000km and non-championship races at Karlskoga, Skarpnack, Montlhery and Kyalami.
Although conceived as the ultimate Group 4 GT40, the authorities considered the M1 sufficiently modified that it should be classed as a Group 6 Prototype. The M1 therefore became a victim of the three-litre engine limit imposed for 1968 and the project was quickly abandoned.
The green light for JWAE’s three-litre Group 6 car was given in mid 1968 with a view to completing a full season in 1969.
Like JWAE’s GT40s, the Mirage M2 would run with backing from Gulf Oil. In 1969, the GT40s were expected to be limited to appearances at the Sebring 12 Hours and Le Mans 24 Hours.
Competition was expected from the formidable Porsche team with their fleet of 908s. Ferrari were also returning to the World Sportscar Championship for 1969 with the handsome new 312 P.
Engine / Gearbox
To power the M2, JWAE had hoped to use the venerable Cosworth DFV that was proving to be the dominant engine in Formula 1. However, despite close ties to Ford, the 1968 allocation of DFVs was already sold out and more engines were not available at any price. Consequently, a temporary alternative was sought.
John Wyer decided to approach BRM with a view to obtaining their Type P101 V12. BRM Chairman and Joint Managing Director, Rubery Owen, was happy to oblige.
The dry-sumped BRM 60° V12 featured an aluminium alloy block and head with chain driven dual overhead camshafts and two valves per cylinder.
Displacement was 2998cc thanks to a bore and stroke of 74.6mm and 57.2mm respectively.
Electrical components and the mechanical fuel-injection system were supplied by Lucas.
With an 11.0:1 compression ratio, peak output was 380bhp at 9750rpm.
Although JWAE did experiment with short F1-style pipes fed through a vertical chimney, the longer exhausts necessitated by the M2’s enclosed bodywork inevitably consumed some power.
Instead of the Hewland DG300 used by BRM in Grand Prix racing, JWAE opted for a beefier ZF 5DS-24 five-speed gearbox as used in their GT40s.
Chassis
The M2’s chassis, body and suspension were designed by Len Terry.
Terry’s firm, Design Auto, devised an aluminium alloy monocoque with 2400mm wheelbase and 1490mm track. Importantly, the M2 did not use the engine as a stressed member; rather, the power unit and rear suspension were mounted on a tubular steel subframe.
Front suspension was via double wishbones. Lower wishbones, top links and twin trailing arms were fitted at the rear. Coil spring / damper units were installed all round along with anti-roll bars at either end.
11.95-inch ventilated disc brakes were supplied by Girling.
The 15-inch diameter centre-lock wheels measured 9.5-inches wide at the front and 12.5-inches wide at the rear. Tyres were supplied by Firestone.
Fuel tanks with a combined capacity of 118-litres were mounted in the sills.
Bodywork
Terry’s fibreglass M2 body was suitably compact and, at just 37-inches high, stood comfortably lower than the GT40.
The nose had small apertures for the oil cooler and brake ducts but no spoilers. Headlights were mounted underneath Plexiglas covers and there was a large vent in between them to discharge airflow from the oil cooler. A bank of three NACA ducts for cockpit ventilation were carved out below the base of the windscreen.
Behind the domed cockpit, Terry added rectangular intakes for the rear-mounted radiators and a fastback rear screen.
The inverted tail fascia resembled that of the Mirage M1; it featured a full width aerofoil and three large openings, the middle of which was an exit point for the four megaphone exhausts.
Interior
Inside, the cockpit was mostly left in bare aluminium.
The rudimentary dash was home to a variety of gauges, warning lights and flick switches. More flick switches were mounted on a central control panel.
The only upholstery was a black corduroy trimmed seat.
All three M2s built by JWAE were right-hand drive with a right-hand gearchange.
Weight / Performance
At 750kg, the M2 was initially a little overweight, but significant reductions were expected during the season.
A top speed of around 200mph was anticipated.
Launch & Testing
The M2 was unveiled during the last week of January 1969.
JWAE took two cars for tests at Daytona and then conducted further running at Thruxton.
JWAE initially shoehorned a Ford V8 from the GT40 into chassis 01 and the BRM engine into chassis 02.
Porsche Exploits New Group 4 Regulations
At the Geneva Motor Show in March 1969, Porsche stunned the racing world.
To stimulate entries for the under-populated Group 4 class, the FIA had announced back in April 1968 that, for 1969, they would slash production requirements from 50 to 25 vehicles.
No-one took too much notice until Porsche unveiled the 917; a five-litre out-and-out Prototype of which at least 25 would be constructed.
The writing was on the wall for the three-litre Group 6 Prototypes.
1969 Brands Hatch 6 Hours
Having hoped to have at least one DFV-powered car ready for the Brands Hatch 6 Hours (April 13th), JWAE announced a week beforehand that a four to six week delay was on the cards.
As a result, only the BRM-engined chassis 02 attended the race which was round three of the 1969 World Sportscar Championship. To make up a two-car entry, JWAE also took one of their Mk1 GT40s.
The Mirage would be driven by Jacky Ickx and Jackie Oliver who had won the previous round at Sebring in a Gulf GT40.
As most testing with the Mirage had been done on high speed circuits, the M2’s handling around the tight and twisty Brands Hatch layout was far from ideal.
It arrived late on Friday and, during Saturday practice, John Wyer considered not starting as he thought the M2 would not be competitive. However, after consultation with the drivers, it was decided to go ahead and the Mirage qualified eleventh.
Pole went to the Porsche 908/02 of Jo Siffert / Brian Redman.
Ickx had a solid start. He was lying seventh with an hour gone and eighth after two.
With Oliver at the wheel though, the car mysteriously cut out on lap 88. It eventually restarted and crawled round to the pits, but was retired with a broken drive shaft.
Jo Siffert and Brian Redman took the win for Porsche.
David Hobbs and Mike Hailwood finished fifth in JWAE’s Gulf GT40 to claim victory in the five-litre Sport class.
Further Testing
As planned, the Monza 1000km and Targa Florio were skipped in favour of more testing at Thruxton.
After the failure at Brands, new GT40 pattern driveshafts were installed. The M2’s spring rates and roll bar settings were also adjusted.
1969 Spa 1000km
With no DFV engines, JWAE arrived at Spa with two BRM-powered M2s for the 1000km race on May 11th.
Ickx / Oliver shared the car they had used at Brands (02). The brand new and virtually untried example was allocated to Hobbs / Hailwood (03).
All three practice days were wet. While Ickx took the opportunity to qualify at the sharp end, neither Hobbs nor Hailwood seemed to enjoy the experience.
The team were kept busy adjusting spring rates and roll bar settings throughout.
The Ickx / Oliver M2 qualified second and took its front row slot between the Lola T70 Mk3B GT of Paul Hawkins and Jo Siffert’s Porsche 908/02 Langheck. Hobbs / Hailwood were back in 14th.
After the rain of practice, race day was dry. Ickx held second at the start, but was quickly passed by Siffert’s Porsche and the Ferrari 312 P of Pedro Rodriguez.
Unfortunately, with just a couple of laps gone, Ickx coasted into the pits with fuel starvation; five laps were spent replacing the fuel pump in an effort to get the car going again. The Belgian did re-emerge, but only completed one-and-a-half more laps before the car packed up for good at Stavelot.
In the sister car, Hobbs and Hailwood had a steady run to eventually finish seventh overall and sixth in the three-litre Prototype class.
Siffert and Redman took their third win of the year for Porsche.
1969 Nurburgring 1000km
Three weeks later, JWAE were ready to give the first DFV-powered Mirage M2 its debut at the Nurburgring 1000km (June 1st).
Compared to chassis 02 and 03 (which used BRM engines), 01 had been configured differently behind the rear bulkhead to accept the wider, shorter Cosworth engine. Although the rear crossmember was new, the suspension layout remained virtually identical.
Cosworth had supplied one of their latest 9-series motors. Careful work with the exhaust manifolds meant there was no power loss.
The DFV was an all-alloy 90° V8 with DOHC four valve heads, dry-sump lubrication and Lucas fuel-injection. It displaced 2993cc thanks to a bore and stroke of 85.7mm and 64.8mm respectively. With an 11.5:1 compression ratio, peak output was 430bhp at 10,000rpm.
Whereas a ZF gearbox had been used in chassis 02 and 03, 01 came with a Hewland DG300.
Weight was unchanged from the BRM-engined variant.
Meanwhile, the BRM engine fitted to chassis 03 had been uprated to the latest P142 type with four valve cylinder heads. As a result, power was now up to 450bhp at 10,750rpm.
Preparation of the cars was completed only minutes before they left for Germany.
Ickx / Oliver would drive the new DFV-powered M2 (01) with Hobbs / Hailwood in the BRM variant (03).
Both M2s were plagued with minor problems during practice.
The Cosworth-powered Ickx / Oliver machine had clutch trouble on Friday and, on Saturday, the engineers found the gearbox wouldn’t go back together properly. As a result, neither driver was able to do more than a few laps.
As for the BRM car, it caught fire in the paddock on the first day and, although damage was minor, only Hobbs got to drive in the afternoon when the handling was still far from right. Hailwood’s opening stint was on Saturday in the pouring rain. As it was his first time around the Nurburgring on four wheels, he took it fairly easy.
Ickx / Oliver qualified eighth with Hobbs / Hailwood 20th.
On pole was the Porsche 908 of Siffert / Redman.
For the first time at the Nurburgring, the race got underway with a rolling instead of Le Mans start.
Ickx moved up from eighth to seventh and put on a real charge to lie fifth by lap three. Hobbs did equally well to go from 20th to twelfth, but was among the first to pit.
Oliver had taken over from Ickx and was eighth at quarter distance when he brought the DFV-powered car in as the steering was playing up. The problem was traced to a loose nut which held the wishbone to the bottom of the upright. It was tightened up and Oliver was sent on his way.
A hailstorm then rolled in which meant the conditions on track became treacherous.
Soon afterwards, both Mirages were out in quick succession.
Oliver retired on lap 16 when he was forced to park up at the Karussell; this time, the other front wishbone had become detached.
Two laps later, Hailwood found himself with no fuel pressure and also came to a halt.
Chassis 01 is Converted to M3 Trim
With just a seventh place finish to show from five outings at three races, JWAE decided to make some wholesale alterations to the M2 before Gulf Racing’s next appearance scheduled for six weeks time at Watkins Glen.
The DFV-powered car underwent a major weight reduction programme including conversion to a pared down Spider body. It was rebranded the Mirage M3.
As for the two BRM-powered M2s, both were retired from active duty and later sold to Jo Siffert.
Text copyright: Supercar Nostalgia
Photo copyright: Gulf Oil - https://www.gulfoilltd.com/
