As for several years past, this year’s Willhire endurance race at Snetterton was qualifying round in the Uniroyal Championship, one of two production saloon series which have become breeding for the British Touring Car Championship. The winning cars look much the same those in Group A, RS Fords leading from BMW M3s at most rounds, yet were important changes to production rules this year which have closed up competition without emasculating lap times. To find out more, first-hand, I revisited the car I shared last year with Kirsh Odor of Janspeed. There was a brief chance to pilot it during some of the pre-event testing sessions which were uncharacteristically wet.
Kieth explained the essential differences between the 287 bhp Sierra we shared last season, and the 1989 winter rebuild of a can which has won six races in 20,000 strenuous road miles. “First of all, we have a lot less horsepower than last season. The introduction electronically-managed boost control has meant that we run under 13 psi maximum boost. In turn that has cut peak power down
45 bhp from last season. “Funnily enough that does not mean the car is necessarily slower in lap times. This year’s car is much better behaved, partly because it doesn’t have great slabs of power arriving suddenly in mid-corner to upset the 205-section road tyres. Just as significant is that we found the best part of a second per lap by switching tyre brands.” There was no commercial advantage behind this change; Odor had free tyres last season, and now has to pay for the Firestone Firehawks.
To illustrate the competitive point, the team showed me that its best lap time of 1989 at Snetterton had been 1 min 17.8 sec, which compared with 1 min 17.4 sec last season. “You can now drive the car flat out from the exit of slow and medium speed esteems whereas before it used to skid all over the place as the boost came in.”
I tried the car on Leda dampers; a far more significant comment than in other British categories since the rules only allow damper changes amongst tight suspension restrictions in production racing. Again, the team has tried most things. I was a fervent advocate of trying to get a gas-pressurised shock absorber such as the Bilstein properly set-up, to provide the an n’ durability that is so important in a race which includes more than 1000 swoops through the right-handed Coram in fourth and fifth gear. When the outside tyre and shock absorber is tortured under loads generated by a constant 100-125 mph in faster corners, and you are braced hard against the fabricated footrest, it is nice to know that nothing is going to give way under the strain.
The Ledas (once again) lasted the course; they do lose their fluid, but they retain enough operational competence on a smooth track to carry on without raising lap times. Complete with 120-litre (26.4-gallon) safety bag tank, the test Sierra was in the kind of condition more commonly associated with concours. From the chrome steady bar across the engine bay to the bare metal flooring, no opportunity to present a cleanly professional face has been lost, and! was almost reluctant to step in and rumple its house-proud cabin. Instead of the standard instruments employed largely last year, I found a barrage of boost meters, including two digital items (one for test purposes, one sealed for RACMSA-authorised officialdom only), plus an enormous “boiler room” device of black needle and white face. The missing boost for 1989 was reflected by a minimum of 12.5 psi, half what we ran on some desperate occasions last season! Secured in a Sparco seat and clamped in Willans harness, I set out in dampish conditions – treacherous enough to demand the occasional twirl upon the posh black suedette Italvolanti wheel in search of some adhesion.
The 1188kg Ford accelerated with the characteristic drone of its side exhaust gradually sharpening from 4000 rpm onward. As in standard trim this 240 bhp edition is extremely flexible, and you can forget any throttle blipping or lower rpm difficulties, a remark that now also extends to the 500 bhp nether regions of machines such as the Andy Rouse Engineering Group A Sierras. Electronic injection and ignition management is a wonderful aid to civilised paddock behaviour. Unlike the 1988 Janspeed and standard engines, this unit had a degree of engine componentry balance. It is not much of a compliment, but it was the smoothest Pintobased engine I have tried, one which positively invites more than 6000 rpm and has explored another 1000 rpm on that with exhilarating energy. Even the gearlever shake seems reduced, and I canter why Kieth used much the same specification for the engine of his roadgoing Sierra RS.
Both Mines and Ferodo friction materials have been employed successfully, and the car actually raced with both types of pad installed. From a driver’s standpoint the pedal was far more positive than last year. However, it is at the end of another hot two-hour session on a dry track that brakes begin to feel their limitations.
After just six laps the Sierra had settled to about the same pace as the Abbott brothers’ Group N Saab 9000 Turbo (which is not at its best in the wet, surprisingly enough), before conditions worsened and put paid to our session.
I had discovered that you could use the power for a lot longer than before, and leave the braking a lot later, assisted by ABS as an extra warning of reduced grip. In fact, the driver could generally treat the Ford a little more like a racing car (higher revs, more precise cornering lines) than the wild dragster we shared in 1988. Any snags to this production paragon? It has some long-distance fuel consumption deficiency that Kieth cannot fathom. In a hard-fought Willhire 25 Hours (Motor Sport, August 1989) he and Barrie Williams finished second, three laps adrift of the Mark Hales/Slim Borgudd Sapphire, and the difference was two extra pit stops for fuel. JW
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