Much of  Imberti’s work to date has been the drawing up and then sourcing of material, and then ensuring that the homologation is in line with the requirements. The homologation form was already quite comprehensive, with an optional close ratio Getrag gearbox alongside the standard ZF unit, and the full range of brake and suspension options one would expect. Initially, the team will be using AP callipers and disc similar to those homologated for the Alfa 75 Turbo, with hubs and wheels to match. Later in the season, probably by June, the further option of the AP twin disc setup is to be used, both front and rear.  

Homologation, however, is still pressing ahead, with fuel injection coming on May 01. Presently, the ProTeam personnel talk of about 360 bhp at 6500 rpm, but already they have found 380 bhp with the carburettors and injection is likely to add a further 20 bhp. For the scrutineers out there, the injection system will be the Weber-Marelli. There are also plans in the pipeline to homologate the 2.0 version of the car on the rationale that, with the turbocharging  of production cars, ultimate power is determined  by the pumping limits of the turbos, rather than the engine capacity. With Group A regulations, there is a sliding scale of power to weigh, a 2.5 turbo (once boosted by the present 1.4 coefficient) comes out at a nominal 3487 cc, and thus has to run with 50 kgs of lead ballast to reach the required 1185 kgs. A 2-litre can run to a limit of 1035 kgs.

In conversation with Elio Imberti, it is quickly clear that the Maserati engines require very little special work, the bottom end, crank, rods and such being especially strong without any modifications. Temperature changes to the twin IHI turbochargers are minimised so that the units run cooler, and their blower output temperature is similarly reduced.

Most of the work at Monza, therefore, was centred on the chassis and the transmission. Given the rush to get the car to the race (due to the political uncertainty over the new FIA series), the car ran very low boost, mainly because the still-standard clutch could not take the power being produced, but also to enable the crew to concentrate on sorting out the chassis. Throughout the meeting, the brake balance was causing extreme problems with too much braking at the rear. This had been solved when the cars appeared at Jarama. Similarly, clutches had become available and the cars were fitted with Sachs competition units.

There were also problems with overheating of the inside of the right rear Dunlop, and this might be more difficult to solve. The only engine problem throughout the weekend was a trivial, though annoyingly delaying, one: the result of tube connections blowing off between the turbo and its intercooler. A potentially catastrophic failure of the left front stub axle threatened to prevent the car finishing the race, just a few laps from the end. Elio’s team of mechanics had the whole stut and brake assembly changed and the brakes (almost!) bled in time for the car to get back on the track for one final lap before the flag came out.

This sort of failure is not too surprising, as this was certainly the first time any Biturbo had run on racong slicks, let alone in a 500 kms race! The metallurgical structure of the stub axle is to be examined to eliminate the same problem recurring.

The entire Monza weekend was very much a last-minute affair, and getting the car to the finish was an achievement. Extraordinarily, given the contorted political situation at present,it did not seem to matter that the car had actually come last overall. The team left Monza with a cup and with maximum Class1 points!

Since Monza, a rigorous testing programme has got under way. The car and the team clearly have the potential, and it would be good for the sport if  Maserati gains the success it deserves, particularly if the Biturbo could defeat the BMW M3 massed panzer divisions.

From Autosport  

April 23,1987

Indietro

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