Champion Defence

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To buy and run a roadgoing Porsche from taxed income is an unattainable dream for the majority of enthusiasts, yet the motorsport world is bulging with over-subscribed Porsche racing series — championships at which amateurs mingle with the professionals, and aspirant pros, to risk their most precious motorised possessions. Recently we have been able to see that this curious phenomenon of apparently endless entry lists in Porsche marque racing exists not just in prosperous West Germany, but also in Great Britain.

We begin with “the home team” and confirmation that the BF Goodrich/ Porsche Club GB Championship continues to act as a major club racing draw. So much so that registrations for participants closed early in 1990, months before the first race, at which pre-qualification races were necessary. We were made aware of this as 1989 BFG/Porsche Club Champion Steve Kevlin, Manager Technical Services, Porsche Cars GB, let us loose in a pre-season test session at Donington in his bold title defender: a strictly open version of the Cabriolet 944 S2. When I say open I mean it, for the car then lacked side windows and there is no intention to ever race it in closed (hood raised) trim.

Why did this cheerful Porsche loyalist of modest manner and extrovert driving style chose the Cabriolet? There were some surprises in the 1989 Champion’s reply. “When the Cabrio was launched last year I said `that would make a nice racing car’ and that feeling was reinforced when I saw the open TVRs in their race series. But the real turning point was almost despite my attitude. When the Porsche Club voted on various 1989/90 rule changes I was one of the committee members who voted against a rule change to permit roll cages as a bolted part of the structure in our Championship. They wanted body shells saved in severe accidents, I thought the move was too far toward the purpose-built racing car. I was outvoted and it led directly to my Cabriolet.

“When I thought about the open car seriously, that roll cage rule had been voted through and we had started building a new 944 Coupe. Now I saw that the convertible could now benefit from a much stronger basic structure, so we sold the Coupe and started all over again!” In this context “we” refers to Steve Kevlin and his loyal mechanics, particularly loyal because they have to live their lives under the nicknames “Pinky and Perky.” Poor reward for the hard work put in under their more formal titles of John Titcombe and Ian Perkins since the December 2nd 1989 start date on the open Porsche racer.

The completed contender competes in the same Class B of the usual A-D quartet of classes in the series that brought Mr Kevlin the 1989 title. For 1990 the S2 version of the 944, whether closed or open, races at an increased minimum of 1190 kg and Steve Kevlin faces far more front engined opposition in 1990. Even the turbocharged 944 is permitted in this class (albeit in earlier 220 bhp trim), but outright wins will continue to be the property of the Class A 911s. Such winners could be turbocharged (3.0 or heavily weight penalised 3.3); the classic 2.7 911 RS (99% are now replicas because of their market values) and the new threat of the 3.6 litre Carrera 2 which is to be raced by AFN and others.

Steve Kevlin continued with some basic construction details. “Remember that Porsche and ASC in West Germany have already ensured that the basic structure of the convertible is strengthened by second skinning the floor and another chassis section beneath the rear seat area. To this our spare time racing team at Reading could add the unique Safety Devices roll cage and bolt it into the body at six points.” Sounds all too simple, does it not? In fact the Safety Devices cage really was a special, because the screen of a 944 Cabrio is more steeply raked than its coupe counterpart and some detail work to blend it and the fascia remained at test time. However the rules forbade any attachment to the suspension mounting points, so that useful bonus had to be foregone in preparation of the roll cage. In standard form the Cabriolet also reflects that basic strengthening activity, for it tips the scales at more than 1350 kg, but it will race at close to the class minimum of 1190 kg; when I drove the dry tank weight was 1206 kg.

One basic move in that lower kerb weight is original in my experience; the team had to remove a 20 kg vibration damper. This tubular weight and slide device is the Porsche answer to unrefined body resonances without the roof, and the mechanics vouched for its road effectiveness: “The Cabriolet is horrible without it, you can really feel, and hear, the difference. “Saving both weight and operational budget is the provision of glassfibre front wings and bonnet; the bonnet was not a good fit and had to be taped into place for the test. The running gear beneath that open coachwork and conscientiously applied tonneau cover is much the same as was employed for Kevlin’s coupé that we assessed in our October 1989 issue. That similarity extends only to the principles, not physically, as Steven Kevlin sold his 1989 car complete.

This means the counterbalanced four cylinder engine at 2990cc (104 x 88mm) is the largest I have dealt with in a production car. It is also one of the most efficient, generating 211 bhp (70.6 bhp per litre), a figure that reflects the presence of a DOHC 16v layout and a 10.9:1 cr and sophisticated Bosch electronic ignition and injection management, yet it is perfectly capable of running 95 RON unleaded.

The Porsche S2 unit is not the most powerful normally aspirated four-cylinder on world sale: BMW generate some 95 bhp per litre from the latest Evolution M3s. Honda provide 100 bhp per litre on home market VTEC four cylinders found in CRX and new Integras. However, when the Honda V-TEC engine is sold in the UK, later this summer, there is unlikely to be more than 150 bhp from 1.6 litres, representing 93.8 bhp per litre.

Where the big Porsche four is unmatched in my experience is for accessible torque. The peak of 207 lb ft at 4100 rpm may not sound remarkable, but when so much of that peak is preserved from 2500 to the 6400 rpm redline, it makes for the sort of mid-range response that will be more familiar to the owners of 3-litre six-cylinders and older American V8s. In a racing context the engine flexibility becomes important in providing balance when an unsuitable gear ratio to corner compromise is faced (which happens twice a lap at Donington), or when racing in a pack and forced off the ideal line. As ever there is a five-speed transaxle at the rear and the regulations demand retention of ratios that allow less than 60 mph in second and 87 mph in third at the 6400 rpm redline. Nevertheless you could expect a standard 944 S2 to sprint from rest to 60 mph in six seconds and this lighter racing cousin felt every bit as quick as that, despite the low mileage engine and transmission in standard trim.

At two sections on the shorter (1.96 mile) Donington layout peak rpm in fourth are attained, and this realises 112 mph; maximum speed on a clear and dry day was 118 mph at 5000 rpm on Starkey’s straight. A road 944 Cabriolet customer would expect one of the increasingly rare de-restricted sections of autobahn unfurling beyond that steeply raked hood and bonnet to bring nearer 150 mph with the hood erect.

For the test sessions we used oversize 245/45 section BF Goodrich R1 tyres on eight inch rims front and rear, but a later pre-season session showed that a seven inch front rim with a 225 section tyre could give better qualifying speed. As in his 1989 coupé, the Kevlin disc brakes are the 4 pistons units formerly fitted to the 220 bhp version of the 944 turbo. There was one important braking change in comparison to last season, the standard provision of ABS anti-lock braking, and this could be identified with a cockpit button to reset rapidly the system, should it pass into failure mode under the exceptional forces of racing circuit use. For our test session we had Porsche “green” asbestos-free pads installed, but standard rear pads were later substituted to counteract the rear end raggedness that both drivers suffered under heavy braking at Donington.

The open cockpit marries standard Porsche 944 instrumentation with welcome racing aides like the Sparco seat, TRW Sabelts and an optional Turbo SE Porsche component steering wheel. The latter three-spoke device is handier than the standard tiller and avoids the usual trap of blocking off the instruments; extra dials included only an engine oil temperature gauge. “Just a precaution from last year,” said team members, adding, “We think we had the cooler wrongly sited last year and so we now like to keep an eye on the temperatures generated in the sump.”

When I arrived at Donington, the car had already lapped the smoothly surfaced twists and challenging gradients of the Derbyshire track in 1.24.81 seconds (83.2 mph average), just about a tenth of a second under the official class lap record. However, there were not the bright smiling faces you might expect under such new car debut circumstances. Even Steve Kevlin’s car control had been extended in controlling the car. That he was then brave enough to let a journalist out was simultaneously flattering and worrying. I was requested to keep “around 6000 rpm” (maximum power is at only 5800 rpm) but was warned that “at the Old Hairpin and the Coppice run onto the main straight” I would be faced with at least 6200 rpm in third and the need for a change the instant I left the corner, or (in the latter case) in mid-corner apex, a practice that is common in production cars, but still unpleasant. I have enough trouble keeping cars on the track with two hands, never mind fiddling about the gearchange and staying on a sharply altered course with one hand. Steve Kevlin did confide that I would be surprised “how different” the cabrio felt to his previous mount, but it was left to me to judge the depth of this statement.

At first I just concentrated on fiddling around, trying to get my feet to attack the brake and clutch pedals at the right angle via seat adjustment. Even so, those initial exploratory laps left me exhilarated with the breezy speed of the open Porsche. I could not see much in the mirrors — comprehensive cage and some missing panes the culprits at this pre-season stage — but it was immediately obvious that this combination was fast enough to cope with the enormous variety (TR3 onward) of production based machinery sharing the circuit. At Redgate I must admit the inversion of a red Escort, one sprouting enormous wheels and tyres beneath extended wheel arches, did little for my confidence in the early laps. Yet this 944 was so invigorating that I was simply moved to get on with it. When the debris had been cleared and the seat moved to suit the short leg pilot, the fun started in earnest. Initially I was startled by its track manners, for it would turn into each slow corner with a sharpness that reminded me of single seater machinery. The snag was that the behaviour of this much stiffened chassis and its similarly stiffer back torsion bars differed from left to right hand corners, all whilst checking gross oversteer that had nothing to do with the usual low gear power slides of the race track rear-drive variety. What appeared to happen was that the combination of uprated springs (the fronts are of the coil type) and chassis had turned it into the biggest racing kart I have driven. So stiff that a rear wheel was lifting through left handers at speeds beyond 100 mph. On a dry day it was simply stimulating fun, the giant four cylinders zipping through the short ratios contemptuously and the white Porsche flicking from steering lock to lock in a style that was not popular with other track occupants. The nervous manners were emphasised by the rear brakes locking up intermittently on the approach to the downhill hairpin (dissuading more than one successful assault in fourth, rather than third) and into the certainty of third gear McLean’s. My usual experience of such spectacular progress is that it is enormously slow, but that was not the case with the Kevlin cabrio. My best time was realised soon after the seat was reset (1m 26.2s/81.9 mph) and it was only the closure of the circuit at the end of the day that reunited Mr Kevlin and his Cabriolet, for the gripping view as it skittered into yet another unlikely attitude set the adrenalin flowing in an addictive manner.

Once the flush of excitement had abated a brisk discussion with the reigning Porsche GB Champion established our common complaints about the vehicle behaviour and the team went on to a second session at Snefterton with a number of important changes to try. Unfortunately the Norfolk circuit had been radically changed over the winter — including a first or second gear (depends on car type) tight deviation before the pits that made any 1989 to 1990 data comparison void, but it did seem that the adoption of a smaller and softer rear anti-roll bar and the substitution of standard rear pads had calmed the patient’s initial twitching whilst allowing Steve Kevlin to remain competitive against a much more numerous (six) turnout of 944 opponents this season.

I can honestly say that I have not had so much fun in a four-cylinder Porsche, but it may be that the drafty sources of such exhilaration slow the car so much on the longer circuit straights that Kevlin is unable to put in a fair title defence. The results of the opening round at Snetterton tended to support this theory, a 911 Turbo 3-litre winning outright, by a dominant six seconds, in the brave hands of Chris Millard. In class B, the lighter 3-litre 911 of Bob Berridge claimed a class win over the 220 bhp 944 Turbo of Nigel Rice, leaving Steve to open his title defence on points earned from third in class. Next on the agenda were the twists of Brands Hatch, but it was also obvious that the tight new engine and transaxle would need some more hard mileage for optimum competitiveness. JW