Guide: Alfa Romeo Giulia TZ
Background
Having won the inaugural 1950 and ‘51 Formula 1 World Championship, Alfa Romeo quit single seater racing owing to the cost of building a new car for 1952 when a two-litre engine limit came into effect.
Instead, the firm embarked upon a Sports car programme with the intention of winning at Le Mans. However, in its original form the resultant C52 ‘Disco Volante’ proved a disaster and although the subsequent 6C 3000 CM most significantly bagged second place in the 1953 Mille Miglia, Alfa management decided to close their competition department at the end of 1953.
During 1961, highly regarded ex-Ferrari and Alfa Romeo engineers Carlo Chiti and Lodovico Chizzola established Delta Auto in Feletto Umberto, Udine. The firm offered engineering services to motor manufacturers and soon picked up a commission from Alfa Romeo who wanted to make an official return to motor racing.
The Milan company already had a production-based 1.6-litre GT car in the very early stages of development, but its real priority had been to get the new Giulia range into production. As work on the Giulia approached its conclusion, Alfa Romeo contracted Delta Auto to help create a purpose-built GT racer to replace the old Giulietta SZ (Sprint Zagato).
The new machine would be conceived for Group 3 GT racing which stipulated a production run of 100 vehicles within a twelve month timeframe.
At the time, GT racing was at an all-time high with the FIA having switched the World Sportscar Championship to focus on these production-based Group 3 Grand Touring cars as opposed to Prototypes. The Prototypes were still eligible to run a limited number of events, but points scored by these more highly developed cars went towards a separate Coupe des Sports.
Zagato unveiled a prototype of the new Giulia TZ at the Turin Motor Show in October 1962. The TZ moniker stood for Tubolare Zagato which referenced the car’s new tubular spaceframe chassis and Zagato coachwork.
On March 5th 1963 Delta Auto was re-branded Autodelta. TZ production began in earnest later that year with the chassis manufactured by SAI in Perugia and the coachwork by Zagato in Milan. Final assembly subsequently took place at the Autodelta works in Udine.
The Giulia TZ was homologated on January 14th 1964, by which time the model had already made a victorious debut at the Monza Coppa FISA.
Shortly afterwards, Autodelta moved from Udine to Milan which enabled the firm to better take advantage of Alfa Romeo’s Balocco test track.
Chassis
The TZ’s special new tubular spaceframe chassis was fashioned from small bore steel tubing by aviation company SAI Ambrosini in Perugia. This arrangement offered considerable weight-saving and rigidity advantages compared to the regular Giulia’s unitary steel bodyshell. The chassis itself weighed just 62.5kg.
At 2200mm, the TZ’s wheelbase was 180mm shorter than the Giulia Sprint and 50mm less than the Sprint Speciale (both of which wore Bertone bodies).
To facilitate a super low profile hood, the TZ’s engine was installed at a 15° angle.
In addition to its trick chassis, the TZ featured significantly uprated suspension which was now fully independent all round.
Up front were double wishbones per side with coil sprung hydraulic shocks. Meanwhile, instead of the standard Giulia’s live rear axle, the TZ incorporated a lower wishbone with the driveshaft acting as the upper link and track control taken care of by the radius rod.
An anti-roll bar was fitted at either end.
The brake system also came in for considerable attention; it now comprised a twin-circuit four-wheel disc set-up instead of the usual drum arrangement out back. The front discs had a 283.5mm diameter while those at the back measured 291.1mm and were mounted inboard next to the differential.
The 15-inch diameter magnesium ten-hole alloy wheels were supplied by Campagnolo and normally used a four-bolt fixing arrangement although a handful of cars came with centre-locking rims. Wheels from 4.5 up to 6.5-inches were available at half-inch intervals.
Mounted behind the rear axle underneath the spare wheel was a long-range 100-litre fuel tank.
Engine / Gearbox
In the TZ’s engine bay was the latest Tipo 00516 iteration of Alfa Romeo’s legendary all-alloy dual overhead camshaft inline ‘four’ designed by Giuseppe Busso.
Bore and stroke dimensions of 78mm and 82mm respectively gave an overall displacement of 1570cc. At this stage, wet-sump lubrication was employed along with single plug ignition.
With a compression ratio of 9.7:1 and two Weber 45 DCOE sidedraught carburettors, peak output was 112bhp at 6500rpm and 98lb-ft at 4200rpm. Units in a similar state of tune could be found in the Giulia Sprint Speciale and Giulia TI Super.
For those customers that wanted the ultimate racing TZ, a higher 11.4:1 compression ratio could be requested that took output to nearer 140bhp.
Transmission was through a single dry-plate clutch and five-speed gearbox for which myriad ratios were available.
Bodywork
The TZ’s body was effectively an evolution of the Giulietta SZ Coda Tronca that had emerged in 1961.
Now even more streamlined and with the tiniest possible frontal area, the TZ looked every inch like a baby Ferrari 250 GTO.
Up front, the air-piercing nose featured all the latest aerodynamic refinements to included covered headlights, semi-recessed sidelights and a bank of upper intake ducts complete with retractable blanking plate. Between the curvaceous front fenders and engine clearance blister, the body sank away to reduce drag. Further back, a distinctive lip at the trailing edge of the single-piece hood deflected air up and over the windscreen.
Rounded flanks were adorned only with release catches for the hood, slim door handles, Zagato emblems and a quick fuel filler cap mounted on the right-side rear fender. A cockpit ventilation vent was also normally added to the right-hand sail panel window.
Door windows could be specified in sliding Plexiglass or conventional roll down glass, but opening quarterlights were always fitted.
The Fastback cockpit housed a large rear screen flanked by a smaller window on each sail panel. This three-window arrangement gave the TZ one of its most distinctive features along with the cavernous Kamm tail which normally came with a black-painted fascia.
Body panels were fabricated entirely from lightweight aluminium to keep weight down.
Interior
Inside, weight-saving was the name of the game which meant little in the way of upholstery, sound deadening or weather proffing.
Aside from a curved instrument binnacle behind the wood-rimmed three-spoke steering wheel, the dash was flat-topped full width item painted stain black. Directly ahead of the driver was a large 10,000rpm rev counted flanked to the left by a small water temperature read out and to the right by an oil pressure gauge.
A large 260kmh speedometer was located in the centre of the dashboard’s vertical fascia along with an array of flick switches, a fuel read out and oil temperature gauge.
Zagato fitted each car with their own lightweight bucket seats that normally came trimmed in dark grey fabric or black vinyl. The only other upholstery was some more black vinyl for the transmission tunnel.
Vinyl door trim panel insertss contained an elasticated map pocket plus simple grab handle and latching mechanisms. Winding window mechanisms were also fitted if sliding Plexiglas windows had not been specified.
Options
In addition to the high compression engine, a choice of gear and axle ratios and a road or race spec. cockpit, TZ customers could request extra wheel sets in various sizes plus additional spot lights for night use.
Weight / Performance
Depending on a car’s specification, a TZ could weigh anything from 640kg to 660kg.
Gear ratios played a major role in top speed and acceleration figures – with the shortest ratio a 0-62mph time of around six seconds was possible while circa 135mph was possible at Le Mans where the longest ratios were typically employed.
Production Changes
In October 1964 Alfa Romeo homologated a dry-sump lubrication system along with bigger intake and exhaust valves (iup from 38.5mm to 41mm and from 42.5mm to 45mm respectively).
In March 1965 a twin plug ignition was made available. By this time peak output figures had surpassed 160bhp.
Towards the end of production, a small number of Tzs were equipped with fibreglass instead of aluminium bodywork to save even more weight.
End of Production
Prototypes aside, TZ production ran from late 1963 to early 1965.
117 examples were built in total, all of which were left-hand drive.
Chassis numbers started at 750001.
The TZ was ultimately replaced by the even more extreme TZ 2 presented at the Turin Motor Show in October 1964.
Competition History
Following its successful debut at the Monza Coppa FISA in November 1963 where Lorenzo Bandini led the four works cars home to claim second overall and win the WHAT class, the TZ went on to have a superb competition career.
Although the Zagato-bodied Alfa was disadvantaged by the Division II category of the 1964 World Sportscar Championship allowing cars of up to two-litres, many event organisers still ran a sub category for up to 1.6-litre cars where the TZ excelled.
That year, the Tubolare Zagato took a long list of class wins, all of which were achieved by the quasi-works Scuderia Sant Ambroeus outfit unless otherwise noted. The year kicked off with victory at the Sebring 12 Hours (Jim Kaser / Chuck Stoddard) which was followed up with a class 1-2-3 finish at the Targa Florio (where Roberto Bussinello / Nino Todaro finished third overall).
Thereafter the TZ took a class 1-2 at the Nurburgring 1000km (Giampiero Biscaldi / Ernst Furtmayr), a class 1-2 at the Le Mans 24 Hours (Roberto Bussinello / Bruno Deserti), a class 1-2 at the Coppa Citta di Enna for privateer Salvatore Panepinto, a class 1-2-3-4 at the Monza Coppa Inter-Europa (Silvio Moser), class wins at the Bridgehampton 500km (for privateers Harry Theodoracopulos / Bob Grossman) and the Tour de France (Jean Rolland / Gabriel Augias for Ecurie Mediterranee) plus a class 1-2- at the Paris 1000km around Montlhery (Silvio Moser / Karl Foitek for Squadra Foitek).
Elsewhere during the 1964 campaign, the TZ notched up an array of domestic and international wins but probably the most significant was outright victory for Jean Rolland and Gabriel Augis who won the Coupes des Alpes outright after a gruelling contest that started on June 22nd and ended six days later on the 27th.
In 1965 Autodelta began racing the TZ 2 which meant the TZ had limited opportunities in a works capacity. Nevertheless, another fine season saw World Championship class wins for Lucien Bianchi / Jean Rolland on the Targa Florio, Boley Pittard at the Spa 500km (for Ian Walker Racing), Carlo Zuccoli / Guido Rava at the Mugello GP, Guido Rava at the Coppa Citta di Enna and privateers Harry Theodoracopulos / Bob Grossman at the Bridgehampton 500km.
Text copyright: Supercar Nostalgia
Photo copyright: Alfa Romeo - https://www.alfaromeo.com
