Marshall's Firenza

Marshall’s Firenza

A study of one of the most successful Special Saloons in British club racing

IF ONE were to sit down and analyse the reason for the changing image of Vauxhall Motors over the last few years, three predominant motor racing factors would emerge: Bill Blydenstein, Gerry Marshall and the racing Firenza which Blydenstein prepares and Marshall drives with such spectacular verve in club Special Saloon car racing. Blydenstein/Marshall successes in their earlier Viva spawned sufficient enthusiasm amongst Vauxhall Dealers for the creation of Dealer Team Vauxhall, which in turn led to important succeses in rallying and increasing use of Vauxhalls amongst privateers in racing and rallying. The whole has led to a much greater respect for the Luton marque amongst motoring sport enthusiasts and persuaded the management to produce its first really sporting car since the 30/98, the “drop-snout” Firenza tested by the Editor, with some reservations, on page 37.

Since its first race at Llandow in September 1971, when it replaced the faithful Viva Blydenstein and Marshall had competed with for the previous few seasons, the racing Firenza has had no less than 58 outright race victories, all with Marshall at the wheel. It began life based on the then newly announced 2-litre Firenza coupe, running under Thames Television colours and now runs under Dealer Team Vauxhall auspices, the original, never-damaged shell re-disguised as the latest “droop-snoot” Firenza by the grafting on of that pertinent nosepiece. There has been gradual development down the years, the most important being the adoption of 2.2 and subsequently 2.3-litre versions of the 16-valve, twin-cam Lotus LV 240 engine in 1973 in place of 2.5 and 2.6-litre adaptations of the production 8-valve, single-overhead-camshaft, in-line four-cylinder engines. Remarkably, the combination of Marshall’s driving skill and Blydenstein’s engineering genius has kept the ageing special saloon Firenza competitive, even in the face of the ferocious new super saloons like John Turner’s 5-litre Chevrolet V8-engined Skoda, the 5-1itre and 4.7-litre Capri V8s of Mick Hill and Tony Strawson, the DFV-engined Capri of Colin Hawker, Ian Richardson’s CanAm McLaren-based Corvair and the Hazlewood/Folwell DAF V8. Blydenstein’s own attempt at building a true super saloon ended abruptly in mid-1974 when the resultant Frank Costin-designed Repco V8-engined Ventora, “Big Bertha”, .which had previously won three races outright and set the outright saloon club circuit saloon record at Silverstone, was written-off at Silverstone by Marshall, when the brakes failed entering a wet Woodcote in pursuit of Frank Gardners Camaro. So the hard-worked Firenza had to be brought back into r4ay for both super saloon car races and special saloon car events. In spite of suffering several unaccustomed mechanical failures, the Firenza’s 1974 race record showed 12 outright wins, nine seconds and a class win and second overall in the Simoniz Special Saloon Car Championship. The writer has a special interest in this Firenze in that he is privileged to have been one of the few people to have driven it apart from Marshall, the others being Paul Frére, in his journalistic capacity, Bill Blydenstein, who competed in a hill-climb with it early in its life, and Gerry Johnstone, Blydenstein’s chief mechanic, who used it to take a class win in a sprint. My chance came at Snetterton in the Spring of 1972, an exciting experience which saw me lap within a couple of seconds of Marshall’s best time on the old long circuit. That was alter I’d subdued myself by managing to spin the Firenza at 110 m.p.h. on the exit from Corams, the first time the car had ever been spun—and in spite of spending most of its life sideways with Marshall, it has been spun only two or three times since. In those days the 2.5-litre, 8-valve engine fitted produced 210 b.h.p. at 6,500 r.p.m. and over 200 lb. ft. torque at a modest 4,500 r.p.m. Today the same 16 cwt. is propelled by 240 to 250 b.h.p. produced by the 16-valve engine at 8,000 r.p.m., the difference in characteristics being shown particularly by the torque figure of 180 to 185 lb. ft. at 6,000 r.p.m. The other thing to have changed over the years, and the two might not he unconnected, was that when I joined the Blydenstein crew for another test session at Snetterton a few weeks ago I was strapped in a specially-fitted passenger seat alongside Marshall instead of behind the wheel! If that driving experience had been exciting, this ride as a passenger was mind-blowing, as anybody who has seen Marshall racing in the wet—and it was wet this day—will realise. Like a 140 m.p.h. ballet-dance on ice, with the 18-stone driver performing pirouettes on the wheel, the dry compound, but hand-cut, Goodyear tyres seemingly well beyond the limit of imaginable adhesion, the tail almost permanently round at 45 to 60 degrees, but the delicate balance between keeping to the soaking tarmac or ploughing through the cornfield preserved by astonishing co-ordination between steering and throttle control. In short, car contrc4 well beyond that which most of us would consider possible. Blydenstein has always been proud of the fact that this racing Firenza contains more of the original manufacturer’s own parts than any of the cars which are competitive against it. The parts are all very much modified, of course, but it does say a lot for the strength of standard Vauxhall components that this should be so. The 2.3-litre engine, for instance, uses a production Firenza cast-iron crankshaft, cross-drilled by the Blydenstein mechanics at their Shepreth, near Royston, Hertfordshire, works to improve lubrication to the crucial bearings. Incidentally, three of those mechanics, Gerry Johnstone, Geoff Hall and Dick Walduck built the car originally and continue to prepare it and accompany It to every race with a pride in it which at times seems almost Maternal! Their pride is shared by newer team members Alan Wright and Peter Henaghan. Blydenstein bought a batch of LV 240 engines in 1972 (they proved to give round about 218 b.h.p. instead of the supposed 240 b.h.p.), these being the 2-litre engines which powered the Lotus 62s, using iron Vauxhall blocks and Lotus twincam heads. For the 1973 season he developed them upon a 2.2-litre capacity, using Vauxhall iron crankshafts and Lotus pistons. They grew to 2.3 when special Vauxhall-sized pistons could be made. Those original Lotus engines are now exhausted and Blydenstein builds his engines from scratch around new, standard, iron Vauxhall blocks, preferring these to the aluminium Jensen-Healey blocks which one assumes could be used. Cosworth forged pistons arc used on cast-iron con-rods which are simply heavy-duty versions of the standard Vauxhall rods. The camshafts have been changed from Laps type to ones of Blydenstein’s own design. A dry sump lubrication system has been fitted since July 1973.

In view of W.B.’s comments about the standard “droop-snoot” Firenza’s ZF gearbox in the road test in this issue, he should find it interesting to note that the racing Firenza’s twin-plate clutch takes the drive to an absolutely standard “droop-snoot” gearbox and by standard I mean ratios as well. Those who find difficulty in selecting gears in the standard car would be staggered by the ease with which Marshall flicks the racer’s lever through its five ratios. With this “overdrive” gearbox a 4.6:1 final drive is fitted in the live rear axle; occasionally a close ratio version of the gearbox has been tried, along with a 4.1:1 axle. It was interesting to hear that, contrary to what one might expect, Marshall makes his rapid starts by using second gear and lots of revs off the line in the dry and first gear in the wet, feeding the revs in gently to get the car rolling so that there will be some traction when all the power is applied.

The most recent significant change to this car has been to move the engine and gearbox rearwards 13½ in. for better weight distribution, now about 50/50 and resulting in much better traction. This has made an immediate reduction of one second a lap at Thruxton with the suspension not yet properly set up to suit.

Many special and super saloons have suspensions based on formula cars. The DTV Firenza pleasingly retains the Vauxhall layout, even if the components are somewhat modified. Ventora bottom arms and hubs are used at the front along with strengthened top arms modified to give negative camber, a high-ratio steering rack, Rose-jointed front castor control arms, a special anti-roll bar, special coil springs and Spax shock-absorbers, fitted at the rear too. Modifications to the live rear axle are very simple, basically, though a brief description hides considerable detail work: stiffer bushes are fitted in the trailing arms, the axle casing is welded and strapped and a limited-slip differential is fitted. Recently it was found that the car was running out of suspension movement so that it was tending to corner on two wheels. This has been cured by raising the front cross-member and raising the rear spring pick-up points into the chassis rails. In conjunction with longer springs (the rears are now standard length, standard rate road springs), this has put back suspension movement and lowered the car by an extra 2 in. Ventilated front discs and a special pedal box with twin master cylinders and a balance bar have been fitted since I drove this Firenza, but the rear drum brakes are the same. Rear discs have been tried and dispensed with mainly because the particular design complicated rush work on the axle at race meetings.

Minilite 13 in. diameter magnesium wheels are of 12 in. section at the rear and 10 in. at the front, shrouded by curvaceous glassfibre wings. The doors, bonnet and boot lid are of glassfibre too, but the body shell itself is standard steel, fitted with Perspex windows and gutted completely, except for necessary extras such as wiring for the centrally mounted switchgear, plumbing to the rear mounted dry sump oil tank and a rectangular alloy instrument panel. A huge centre console covers the re-positioned engine and gearbox and the final touch is added by an electrically-heated front screen to prevent misting-up, the bugbear of saloon car drivers in wet weather races.

Ageing though it may be, Bill Blydenstein confidently believes that this remarkable Firenza is good for another couple of seasons of competitive racing for DTV. Development is by no means at an end, he feels, and when Gerry Marshall returns to the fray with the car this season he should have the benefit of even better handling with the car another 2 in, closer to the ground. Under the new agreement between DTV and Castrol, it will enter the new year in Team Castrol colours.

—C.R.