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This article was first published in January 1999.
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Andrew Cavelli of Adelaide's Quickco Motorsport has been a Ford fan from way back. He's also had a heap of experience in modifying and race-preparing Escorts for both himself and his customers. Around mid-1998, Andrew bought a 1970 Escort 2-door with the intention of replicating a BDA racecar and competing in 'Classic Rally' style tarmac events.
Those unfamiliar with the mechanical pedigree of the all-conquering Escorts of the '70s might be asking - so what's a BDA Escort, anyway? Fast-rewind back to the early Sixties. Ford in the UK wanted more power from their Cortina engine and decided to use a Lotus-designed twin cam, 8-valve head on the Ford four. The Lotus Cortina was the result - a fast little car that performed well on both the road and the track. When the Escort replaced the Cortina, the engine made the jump into the new body. But while the Lotus twin cam was a huge success, by this time its power output limit had been reached. Enter Cosworth with another head for the 1600 Ford
block - this time a 4 valves per cylinder jobbie christened the BDA.
The initials were in reference to the hi-po car's engine twin cams being belt driven ('BD'), while the 'A' simply identified it as the Series A. The engine used solid skirt flat top pistons to give a high compression ratio of 10.0:1 and the Cosworth-designed aluminium head featured valves that sat at 45 degree incline, forming a semi-hemispherical combustion chamber. The intake manifold was cast integrally
and was designed to accept a choice of either dual Weber 40DCOE/48 carbs or Dellorto 40 DHLA/Es.
After Cosworth finished integrating the package, it gave an impressive 115hp at 6500rpm and a torque peak of 112ft-lb at 4000. It could sprint the 'Type 49' Escort to 60mph in around 8.5 seconds. But what was most relevant was its tuning potential in motorsport. By enlarging valve sizes, changing the cams and slightly raising the compression ratio, a lot more power was released. All right then, the BDA was a pretty potent piece of machinery...
The engine fitted to the car that you see here is the Cosworth-Ford BDA twin-cam, but the displacement in this beast has grown from 1600 to 1800cc. Assembled by both Andrew and his co-driver Mike Dale, the bottom-end now uses the latest and greatest billet steel crank that delivers a stroke of 82mm. The bores are 83.5mm in diameter and in these slide forged Omega pistons that push the compression ratio up to 12.5:1. Steel Carillo-style 'H-beam' conrods are bolted together with ARP items. Vandervel rings and bearings are used throughout the engine.
A Formula Ford dry sump system ensures the are no oil surge problems inside the engine, and also relieves a few more ponies due to the lack of crankshaft windage. Also on the topic of engine safety, a custom one-off aluminium radiator keeps a lid on the twin-cam's fever. The work-of-art Cosworth head got treated to a pair of Kent billet cams that deliver a total of 400 thou lift and definitely give the car a purposeful idle. While the head was off, it underwent some
mandatory porting and polishing (enough to flow 265hp) and was treated to moderately larger valves - an effective modification as proven in the 1970's rally scene.
Equally competition-oriented is the raunchy induction system which uses twin 45mm Webers mounted on the standard RS intake manifold. A pair of Carter pumps located in the boot provide a 6psi fuel supply to the carburettors. To achieve the best results, the carbs have been thoroughly tuned and re-jetted while the car was strapped down on a chassis dyno. The ignition side of things is taken care of by a high energy ignition with a magnetic pick-up, plus Top Gun leads and NGK '7' spark plugs inside the combustion chamber. On the exhaust side of the head, there's a custom set of hand made tuned-length extractors that use 1¾ -inch primaries flowing into a mandrel bent 2½ -inch system with a single muffler.
So how much power has been pulled from this little Pommy Ford four pot? Andrew has had the car dyno'd at Turbo Tune and seen 125kW (167.5hp) at the wheels - which has been
translated by the guys to around 164kW (220hp) at the flywheel! Mike says the engine was built more for torque than outright power, but 220hp sure isn't anything to be sneezed at in a 900-odd kg (1980lb) car!
Backing the strong four is a twin-plate AP racing clutch and pressure plate, plus a Quickco steel flywheel which transfers torque to a 5-speed Quaife gearbox containing straight-cut close-ratio gears. The standard RS1600 hydraulic clutch actuation has been fitted. Such an elaborate Quaife gearbox set-up is unlikely to ever give problems!
Putting the 1800's mumbo to the tarmac is a competition-style full floating ZF LSD (commonly dubbed the 'baby atlas') spinning a 4.6:1 ratio. To the centre of the diff connect billet Romac axles which reach outward to a special Quickco rear brake conversion kit. This comprises 280mm solid discs and single piston calipers, while at the front are the reputable AP 4 pot calipers biting massive 300mm vented discs. A racing set of carbon/metallic pads gives the braking system the desired stopping abilities.
No brake booster is used, as there is a Quickco adjustable pedal box along with a brake balance bar control located inside the cabin. A brake booster is not as effective in this type of car, as at any one time there can be minimal engine vacuum available to assist the pedal. But to aid tight corner manoeuvres, a hydraulic handbrake helps Andrew to tuck the nose in and step the back end out.
Designed for tarmac use, the suspension setting is usually very low, but in the photos shown here the car has been raised about 2 inches. It uses adjustable Koni shocks front and rear, a front Quickco adjustable short-stroke coil-over arrangement plus an alloy anti-dive kit also at the front. At the front, around 2-2½ degrees of negative camber is dialed in along with about 1mm of toe-in and 3½ degrees positive castor. Atop each strut tower rests a spherical bearing to replace the original rubbers, which don't offer the same amount of driver control.
The rear end is made up of a Quickco fabricated system that includes single leaf springs, two top radius arms and an adjustable Panhard rod to maintain the correct geometry. The rear shock towers have also been turreted to achieve the correct shocker angle. The car rides on a set of Performance 14x7 alloy wheels wearing 205/60 Falken GRBs for maximum possible traction.
On-board is a typical example of a purebred racecar - nothing that's unnecessary has been spared the flick! The standard "double bubble" dashboard remains in place and contains a comprehensive array of gauges, while fronting the front seat passenger is a Terratrip rally computer, Halda rally Tripmaster and various switches. Andrew and co-driver Mike sit in a pair of carbon fibre/Kevlar Velo GP200 race seats and communicate on the Terraphone intercom system while being safely strapped in by 6-point OMP harnesses.
There's also that serious looking Safety Devices steel roll cage installed with extra strengthening added. In addition, there's a fire extinguisher system installed to the car, with two nozzles inside the cabin and another two under the bonnet - intended to save the Cosworth gem in the event of a fire. To keep the feel of the era when the original cars stood in the spotlight, the car has been sprayed in BDA Escort period colours: they came in either white, white or white! Within the boot resides the battery (as it could no longer be fitted in BDA Escort engine bay), along with a 60-litre fuel tank containing 100 octane and the dry sump system components.
After the exhaustive transformation of what was originally a stock-standard Escort (remember?), had been completed, it was booted straight out into the rough-and-tough of competition. Realistically aiming to manage only a Top 10 placing, Andrew and co-driver Mike Dale were only too pleased to learn they had what it took to convincingly maul the opposition in the annual Adelaide Classic Rally. Against Ferrari V12s, a V8 Iso Rivolta, Falcon GTs and other classic performance cars, the Escort just wiped them!
Then it was off to the Mallala circuit where we photographed the car in action. Even though the car had never been raced there before, it was soon reeling off low 1.21/1.22s, a time comparable to some of the vastly experienced club racers that make it out there at every meeting...
Huh? Isn't a car supposed to gradually work its way to the top?!
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