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.....years, seems likely to prove very competitive within the limited budget areas of future Category A requirements - and this is very much the area in which young aspiring talent must be found. The Italians have already learnt this lesson with the Ritmo.
What then is the catch, and why is John Taylor such an enthusiastic advocate of Fiesta? "I'm a supporter because I really believe that it's the right way to go. The potential is definitely there, and I'd love to have been driving it. I think we'd already have had much greater recognition for Fiesta had we been based in France, possessed radial tyres, and been contesting French mountain tarmac events like Renault have done.
"Back in 78, we proved that the car could, take it - we put 180bhp through a standard transmission and driveshafts. It was only when we tried too much negative camber without realising what that would do to the ball joints that something broke."
What then does go wrong? "So far, very little. Drivers tend to crash the gears because of the need for a left foot braking technique, but that's all a question of experience, and at present it merely results in worn synchro rings. But so far this year we've had a solitary rear stub axle failure and the odd synchromesh difficulties, but they haven't stopped us.
"Perhaps Tim's not going quick enough now - he hasn't marked the car in six events!"
Brise may not be going quick enough, but he's going quicker than he was at the start of the year - that much is a certainty. The Haynes Fiesta was between five and six seconds per mile off the pace of national status Escorts then. Now, in July, the gap is down to one or two seconds, and has occasionally crossed 'into the black'. Taylor confidently expects Brise to be on a par with such RWD opposition by the end of the year.
So it's becoming clear that Fiesta, to some extent at least, suffers in terms of results due to the inexperience ot its drivers. Watch Stig Blomqvist coming into a corner. He brakes and changes down simultaneously, as in a conventional rally car, but instead of inducing oversteer and balancing it on the steering, he tends to brake and accelerate at the same time in order to maintain whatever car attitude he wants; and always there is power with slight understeer just prior to the exit. It's a technique which can be relatively simple in long sweeping corners, but very lew drivers, Stig and perhaps Per apart, seem to be capable of keeping the momentum going in narrow, tight and/or twisty loose sections. Once large applications of steering lock are applied, time is inevitably lost.
The Haynes/Taylor/Brise programme with Fiesta has at least proved the limits to which it is possible to go, at the earliest opportunity. Essentially, because the rear of the car is pivoting around the front, the back axle takes a lot of sideways inertia, which means that attention to Panhard rod brackets is as important as the front suspension; but it is generally agreed by all concerned that Fiesta (or FWD for that matter) requires far more attention in the build stage, and much more delicate setting-up of suspension components than any RWD animal.
The secrets of the car aren't really secrets at all; the Ferguson designed viscious fluid LSD, on which it is possible to alter the settings of valves which actuate the locking device, is certainly one of them, in that it appears to be far easier to live with (from the driver's angle) than pawl type units, but the other major clue to Fiesta competition success lies in the work carried out to front and rear suspension by Len Bailey on behalf of Ford. Meanwhile, if further proof were required of Fiesta's competition potential, look no further than Debenhams' Fiesta races. Fifty eight seconds is now a respectable lap time for these (essentially AVO X-pack derived) cars - a time which compares interestingly with the previous year's Escort Sport models fitted with engines of the same specification -62.3 seconds. (However it should be added that the Escort is marginally heavier).
Len Bailey's collaboration with John Griffiths at Boreham has produced results, but it has taken something like a trebling of chassis stiffness (although only about 4lbs extra weight) to achieve it. In terms of competition, the Fiesta is a floppy chassis which requires to have geometry superimposed on it - the Germans discovered early in its life that merely by making up and fitting some attractive diecast wheels to the car, the resulting beast wouldn't even drive in a straight line; so Bailey's task, in essence, was to.design 31 compromise suspension so that a wide range of wheels could be used with minimal disturbance to handling qualities. His design has minimised changes in king pin offset, which reduces the amount of steering kickback and problems of suspension jack-up, because, as you swing say a two inch 'outset' around a strut, so you also move the car up and down, or jack it up.
To achieve his aims. Bailey has designed a system of specially reinforced, wide based triangulated wishbones. These tubular 'wheel location arms' replace the standard bottom arms together with new aluminium uprights, front hubs, uprated bearing assemblies and carriers, plus a new front anti-roll bar with revised supporting brackets. Heavy duty ventilated discs with four pot calipers complete the picture at the front; while at the rear there are marginally smaller vented discs with two pot calipers and an additional mechanical/hydrualic caliper for the handbrake - all G2I
Modifications to the rear suspension include reinforcement of the axle, uprated bearings and hubs, additional brackets for the disc brake calipers, and tubular radius rods located by the familiar rose joint/heavy duty bush arrangement seen on Escorts for many years. A heavy duty Panhard rod completes the picture.
The wheels fit very tightly to achieve the correct geometry, but it is now possible to fit any size of wheel between five and eight inches in width without suffering highly significant, and crippling, geometry changes. In fact John Taylor's team now run seven inch rims and 175 section tyres on the loose, having taken off all the negative camber and discovered that the car tends to steer straighter without it.
One of the essential problems associated with FWD is that the maximum side thrust of the tyre is diluted by steering thrust; an increase in wheel loading reduces side thrust; or put another way, the combination of applying power and turning-in produces progressively more understeer.
Bailey was very conscious of the fact that tyre engineers can now achieve virtually as much as chassis engineers, and has thus attempted to make the car as readily adaptable to as wide a range of tyre widths and constructions as possible. The task has been accomplished by using a much tougher and specially made SKF bearing housed in an immaculate alloy casting and capable of taking considerably uprated driveshafts. Since then, (and all these parameters were achieved before Monte '79) development has centred around experiments with camber and caster, along with attempts to improve the weight distribution.
When any discussion centres around 'improving weight distribution' or 'moving the weight around' one is always reminded of the cynical thought that what's really meant is that the wheelbase is being surrepticiously altered. Undoubtedly Ford has looked closely at this area. It may well be that Erika, the new Escort, provides a superior answer, if only for reasons of its greater wheelbase and different rear suspension. But in the meantime it's very easy to play the illegal wheelbase game, as Ford, with so much experience of G1 racing etc., are no doubt well aware.
Another pre-requisite of the Bailey design was to minimise the difference between front and rear roll centres - lowering the front roll centre also assists handling by inhibiting the jack-up tendencies of the loaded wheel; and lowering the front roll centre meant similar work at the rear - as far as was possible within the G2 regulations framework, of course I
Nevertheless, Bailey is convinced that FWD can be a bit like 4WD in that the power that can be effectively transmitted through the front wheels is limited. That being the case, and all other chassis considerations being equal, the car with the greatest power-to-weight ratio must win.
If one makes a further presumption that a competitive G2 (call it category A, if you like) car will require at least 230bhp, then Fiesta, even with a weight advantage, may be up against it in the future; especially if, like Bailey, you are of the opinion that about 230bhp is the point at which FWD power transmission begins to run into deep water. "I'm sure I could design an FWD car, for competition or anything else, as well as anyone; but that's only OK as long as everyone else is using FWD."
In the meantime, Fiesta with instantly adjustable caster can be effectively tailored to differing road conditions. It has an enthusiastic band of supporters and there's no doubt that had Ford handled its initial competition forays with a bit more flair and imagination, it would have met with a far better reception than it has done.
We're reasonably convinced that it will be a clubman's mainstay in the future, but we're equally convinced that Ford is looking hard at the 200-off Category B - although we still doubt that even if the company were to choose this route that it would deviate significantly from mainstream production; ie contemolate a Renault 5 Turbo.
New Cortina, (RWD) scheduled in '81, is an obvious vehicle, and in South African specification, evaluation is already taking place; but there are marketing problems to be overcome even here, with generic name changes (Taunus or Cortina?) tending to dilute impact.
Then again, at least 80 percent of Cortina/Taunus sales go to the fleet market; in marketing terms, does such a fact tell against using Cortina as a competition vehicle? And one particular version of the new Escort looks the part.
The jigsaw does not seem to have settledinto place as yet; but Fiesta as a competition car is here to stay, that's surely a certainty. PN
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