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.....car, but this is incidental to their suitability for competition.
At the rear new suspension parts are confined to the lower tubular steel location rods with Rose joints at one end. Boreham have now reduced their use of Rose joints in general feeling that too much of a good thing leads to, at least, premature wear and service demands. Of course Bilstein gas-filled dampers are fitted to this factory Ford, but they are directly interchangeable with production components. Looking at the damper central shafts on the rear you can see they are doing some location work by the extra-sturdy diameter of the central tube. New coil springs were made up, this light car asking only 170 Ib. front and 150 Ib. rears to provide handling that was generally widely praised.
Braking is an area of continuing development on the Fiesta at present. The cars actually went to the Monte with AP 4-pot calipers that had to be removed to change pads, and that demanded some extra machining inside those four-spoke alloy wheels. A new Girling AR5 caliper will be called into use on the front and this will allow pad changes in situ. Luckily Ford only had to change pads once on the Monte and that was in a 30 minute service area!
The factory Fiesta eventually used 4-wheel ventilated disc brakes some 10 in. in diameter at the front and around 9 in. at the rear: the handbrake was less of a problem than is often the case on Escorts because the rear wheels are so lightly laden.
Talking about setting up the Fiesta overall Meade commented, "anyone can set up an Escort reasonably, to set up a Fiesta requires a lot more knowledge. Some things are critical. You cannot play around with ride height readily because you alter the angles on the driveshafts with a consequent mechanical risk. Another inch on wheel offset can turn a good Fiesta into a right beast, twitching all over the place. That is because of the negative scrub geometry - thus the built up "hubs" inside our front wheels. Geometry is all important and that is one of the major improvements we have been able to make."
Meade makes the point that putting wider wheels on a production Fiesta can upset the handling and also cause malfunction in the cross-linked braking system. The factory used a variety of Dunlops on five, six and eight inch alloy wheels of 13 in. diameter. "We had always expected to use wider wheels at the front than at the rear with FWD," recalls Meade, "and that is how it turned out when we went testing, it's simply the better way."
One of the least satisfactory aspects of the Fiesta was the clutch operation. There is nothing wrong with the four-sintered panels on the clutch plate itself, but a bolt on the activating fork showed a tendency to shear (it can happen on the road cars too, but the extra loads involved on the competition unit obviously do not help!) and there was the need for changes during the rally.
As an old Boreham hand, Meade also looks at Fiesta gearbox removal with disfavour. The Escort has a quick release layout for its ZF five-speed, but on the Fiesta it would take three-quarters of an hour: "We'll get it down to 20 minutes, you see," Meade prophesied with a chuckle.
Incidentally there are four final drive overall ratios for the competition Fiesta at present. Together with the top speed they provide on Dunlop Az tyres at 8,000 engine crankshaft r.p.m., they are: . 5.91:1 (87 m.p.h.); 5.31:1 (95 m.p.h.); 4.85:1 (105 m.p.h.) and 4.36:1 (114 m.p.h.). The first ratio was the one used on the Monte. Gear ratios no longer have to be individually homologated.
I have left the 1,599 c.c. four-cylinder engine until last because that is a familiar item from Ford's past - when it was usually homologated at i,601 c.c.! - and it amounts to a pushrod Kent crossflow in a trim not far away from the old Clubman's racing specification. The motors were built by Brian Hart at Harlow for the event and, I understand from Ford, incorporated Cosworth pistons allowing 10:1 CR (approximate); "selected" connecting rods; a Gp2 iron crankshaft; Cosworth A6 camshaft profile and the assistance of twin double choke Weber 45 DCOE carburetters upon new inlet manifolding. New exhaust manifolding was also provided and the complete package was reckoned to produce 155 b.h.p. at a safe maximum of 8,500 r.p.m.
Since the Clark Monte car also tested with an 1800 BDA i6-valve engine installed, it seemed fair'to ask what the engine future held for Fiesta. Surely it can only be a class-winning car with 800 kg. and around 160 b.h.p.? That has not been the Ford style since the advent of the Escort.
As far as I could gather the future does lie with the 1600 pushrod. It may grow fuel injection -the problem is where to mount the injection pump as the crossmember gets in the way on this transversely-mounted motor. They will also be tidying up the fact that the exhaust manifold has to be removed to get at the alternator: that component often needs to be reached in a hurry on a rally car....
The Cosworth Ford :6-valve engine is out for the Fiesta unless Peter Ashcroft can persuade the powers that be to let a special run of 400 road-equipped BDA Fiestas into limited production. When I wrote this it seemed unlikely: I even heard a rumour that Ford wanted to produce a rear or mid-engined Fiesta BDA to give Renault a run for their money with that R5-turbo we have discussed recently! That seems even more unlikely to happen.
One thing's plain. The factory Escort is in its last season. They are talking about its final rally at the factory and the future in small Fords is about front drive machines. It is simply too early to tell whether this means the end of Ford as front-runners on international rallies - they could use other models in the range if overall wins are still the target and financially within reach. Alternatively a fuel-injection 1800 version of the Fiesta in pushrod form would be an effective weapon in the eighties when it is quite possible that only less-radically-modified cars of Group i and 3 will be permitted. Soon, say the prophets, you will not be able legally to run a Gp4 car on the road (an essential part of rallying of course) and when that day comes a Group i Fiesta (currently under development) will be just the job!
Personally I'll miss all the sideways motoring, but I expect Vatanen will have an answer with practice! - J.W.
Captions -
Top-Left - A cut-away view of the new Group 2 rally Fiesta and, below, a tailpiece of Clark on the Monte.
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