Battle of the hot Ford Escorts: Twin Cam vs RS1600

| 3 Mar 2014

Bury your right foot and the rich, distinctive induction note evolves into an addictive twin-cam scream. Suddenly you’re Roger Clark, thrashing his mud-spattered Ford through the misty Welsh forests on his way to adding another RAC trophy to the Escort’s cabinet. Few cars command as much affection among rally fans as Ford’s Twin Cam Escort and its BDA-engined successor, the RS1600. And it’s easy to see why: these unassuming saloons packed enough punch in their day to propel Ford’s Competitions Dept to the top of its game, with Mk1 Escorts bringing home two World Rally Manufacturers’ Championships and racking up a string of international victories for such legends as Clark, Hannu Mikkola and Timo Mäkinen. Its success was enough to kick-start Ford’s famous Advanced Vehicle Operations plant and Rallye Sport performance dynasty.

It was the wolf-in-sheep’s-clothing effect of slotting a potent engine into the ubiquitous small saloon that fuelled the public devotion for fast Fords and the marque rapidly developed a reputation for giving run-of-the-mill cars a serious dose of zing. The roots of this formula lie in the Lotus Cortina and it survives to this day in the recently launched 296bhp Focus RS.

Back to 1967 and the ‘Blimey’ car, as the Twin Cam was nicknamed, was taking shape. When Ford motor sport engineer Bill Meade saw an Escort prototype being tested, he blurted out: “Blimey, one of those things would go like hell with a Twin Cam in it.” Given the phenomenal Touring Car success of the Lotus Cortina in the hands of Jim Clark and others, the performance advantages of Lotus power were obvious. And with an Escort weighing around 300lb less than a Cortina, it was bound to be a weapon of note. 

Team manager Henry Taylor agreed and the pair hatched a plan for the engine and running gear from a Lotus Cortina to be shoehorned into a prototype body. The transplant surgery took place over a weekend and there were no drawings or calculations – just several determined volunteers and a 4lb hammer for some judicious alterations to the inner wings and gearbox tunnel. Mechanically, the biggest change was the adoption of radius arms to keep the beefier rear axle in check and Capri front MacPherson struts with disc brakes. The front suspension got a forward-mounted anti-roll bar and there were wider 13in wheels all round. The battery was relocated to the boot to free up space in the engine bay (and improve weight distribution), but the engine still had to be canted over to allow the airbox to fit. Visual tweaks were limited to a lower stance, a black-painted grille and a split front bumper to boost air flow to the oil cooler.

Production kicked off in early 1968 – less than a year after that famous weekend of spannering – at the same time as the standard model hit the streets. Hand-assembled separately at Ford’s Halewood plant, the Twin Cam used a strengthened 1300GT two-door shell, known as the Type 49. With 109.5bhp on tap – in place of the 1300GT’s 71bhp – and just 785kg to lug around, the Twin Cam’s performance was always going to be impressive. Motor recorded a top speed of 111mph and 0-60mph in 8.7 secs when it got its hands on a car in April 1968. Motor sport success followed the same month, with Clark’s victory on the Circuit of Ireland planting the seeds of the Escort’s formidable reputation. 

A thousand cars had to be built to homologate the Twin Cam for Group 2 and some – such as this pair – inevitably slipped out the stage door and lived their entire lives as road cars. Turn the key and you get a taste of why Ford was on to such a winner. The Lotus Twin Cam fires with a rich, flatulent gurgle that hints at plenty of bite. It spits and coughs when cold, but once warm it’ll pull cleanly thanks to a surprising dollop of bottom-end torque. Snick the tight and wonderfully short gearshift into second and you’re rewarded with a burst of induction noise from the four chokes of the sidedraught Weber carbs before the exhaust explodes with a tinny bark. 

Initially, there’s little to distinguish it from a regular Escort other than a firmer feel over bumpy stretches, but that perception quickly evaporates as you push your foot all the way and feel the tail hunker down. From 4000rpm, the Twin Cam snarls with all the vigour of a Staffordshire Bull Terrier straining at its leash.

The car’s road manners are equally playful, thanks to a simple, leaf-sprung rear end that you can waggle on demand. It’s chuckable, but a healthy dose of negative camber on the front wheels keeps the nose in check as you turn in. The steering is wonderfully precise compared to a standard Escort’s, although it’s all too easy to overdo it in tight corners. And corners are what these cars are all about: both have longer gearing (3.77:1 in place of a standard Escort’s 4.25:1 final-drive ratio) but their four-speed ’boxes (five-speed was a rare option on the RS) still puts the revs up at 4000rpm at the national limit, making any sustained cruising fatiguing. 

The ‘Twink’ may have hit the ground running, but Ford wasn’t distracted by its success. The famous Harry Mundy-designed Lotus engine was getting long in the tooth by the late ’60s and Ford knew that it needed a new engine to keep the Escort ahead of the likes of Porsche in the international rally scene. Another hybrid engine was the answer – this time from Cosworth, which developed a twin-cam, 16-valve aluminium cylinder head for the 1599cc Kent motor. With sturdier, belt-driven valvegear, the prosaically named BDA – Belt Drive, Series A – unit was good for 120bhp and 112lb ft, startling figures for a 1.6-litre when the RS1600 superseded the Twin Cam in 1971. With the demand ramping up following the Twin Cam’s competition success, production moved to Ford’s newly established AVO plant at Aveley with the last 200 examples (including this car) boasting a lighter, all-alloy engine designed by Brian Hart to enable a capacity increase in competition cars.

By that time, Ford’s marketeers had latched on to the value of the RS brand and offered a raft of accessories under its Rallye Sport dealer network, including the ‘Custom Pack’ specified for this RS1600, the last made. That meant wood veneer trim (since removed), RS-badged reclining Recaro seats and steering wheel, plus a PYE medium-wave radio. The RS1600 also had a heated rear window and hazard warning flashers, with buyers at last able to choose the colour as the Twin Cam’s low-key Ermine White gave way to shades such as this RS’s striking Sebring Red. It’s a searing hue that perfectly complements the car’s Coke-bottle lines, giving it the presence of a baby Dukes of Hazzard Charger.

The added refinements make the RS1600 driving experience a touch more insulated as the thicker carpets and cloth trim dampen road noise. The engine is smoother, too, with the extra breathing of the multi-valve layout meaning the tacho needle flicks around the dial like a superbike’s when you hit 4000rpm. But the biggest impression is the lack of fuss: the belt-driven valvegear produces less mechanical chatter and feels bulletproof as you pile on the revs. It’ll still howl like a hyena, mind – once you’ve overcome the unit’s lack of low-down torque – but it’s decidedly more sophisticated.

In contrast, it’s the Twin Cam’s simplicity that enthrals. It doesn’t have the exquisite mechanical refinement of an Alfa twin-cam but feels unburstable, a tough nut that can be thrashed with impunity as if you’re on a rally stage yet still take you to the shops on the way home. The stark interior, with its fixed vinyl seats and simple dashboard finish, adds to the sense of purpose and the no-frills mentality of its creators.

Both are huge fun to drive, though, thanks to their sharp, light controls and precise steering. Ultimately there’s little difference in performance, too, although the torque of the Twin Cam makes it feel punchier initially, while the RS has decidedly more kick if you let it wind all the way to its 6500rpm redline (500rpm higher than the Twin Cam will safely handle). By then the BDA engine delivers an almost primal scream, the live-axle rear struggling to cope as the power catapults you forwards like a cheetah escaping from a cage. It’s that sudden step-change in performance at the top end that meant the RS continued where the Twin Cam left off, clinching the 1972 Safari Rally and three RAC Rally victories in a row, beginning that same year.

The RS1600’s successes led to further developments in the Escort line. Initially they came in the form of the 2-litre Pinto-engined RS2000, which added torque and tractability without the production cost and regular tuning requirements of the multi-valve unit. But it also diluted the recipe, with its more luxurious interior aimed at business execs with a sporting streak rather than out-and-out road racers. Ford got its eye back on the ball with the Mk2 RS1800 that followed in 1975, which reverted to the BDA unit in larger, 1800cc form. By that stage, Ford’s domination of the international rally circuit had given the RS global appeal and the badge was applied to just about every sporting derivative to come off the drawing boards at Dagenham.

Today, both Twin Cam and RS1600 remain immensely usable and seriously competitive on the historic rally scene. They’re both blue-chip investments, too, with decent examples easily commanding £20,000-plus. That’s assuming, of course, that you can find an owner who’s willing to part with one. Whether you fall for the kudos of the seminal, Lotus-engined Twin Cam with its rich, tinny bark or prefer the screaming persona of the magnificent BDA lump, either Escort is guaranteed to turn every drive into a rally stage. Me? I can’t help falling for the Twin Cam’s restrained approach and characterful engine. It’s the original fast Ford.

UNBEATABLE – THE ESCORTS ON STAGE

The Escort’s combination of pace, agility and rugged reliability helped it to reign supreme in the hands of both works and privateer rally teams. “They were a lot like the Mini had been – nothing else offered that sort of performance and was so easy to work on,” says former works driver and current BP-Ford World Rally team boss Malcolm Wilson. “They made competing easy.” Victory on the 1968 Circuit of Ireland was repeated on the Tulip, Austrian Alpine and the Acropolis rallies – all within eight weeks. 

The same season, a young Hannu Mikkola blasted to victory on the Finnish 1000 Lakes Rally (an event the Escort would win five times) and Ford clinched the Manufacturers’ Championship in the Twin Cam’s first season – an achievement it repeated in 1969. 

Stuart Turner, Ford Director of Motorsport from 1970 and boss of AVO from 1972-’75, was one of the forces behind the RS1600. “They were brilliant to drive,” he recalls, “and even better to watch in action.” Key to the Escort’s success, says Turner, was tireless development: “It had an homologation form to read along with Shakespeare and the Bible.” Turner cites the RAC Rally victories of Clark and Mason (1972) and Mäkinen and Liddon (1973/’74) as its best performances. 

In 1972, Mikkola and Gunnar Palm proved the RS1600’s breadth of ability by becoming the first European team to win the gruelling East African Safari Rally. But arguably an even greater achievement was an overhead-valve Escort’s victory on the 16,000-mile London to Mexico World Cup Rally two years earlier, with five cars finishing in the top eight. Ford capitalised on that win with a clever piece of marketing: the Mexico. This Kent-engined road-racer sold by the thousand as Escort fever reached new heights. 

The model’s success continued with the Mk2 RS1800, which helped Björn Waldegård scoop the WRC Drivers’ crown – and Ford the Manufacturers’ title – in 1979. By then, the Escort was part of rallying lore. “Nothing sounds better than a Twin Cam or a BDA at full chat through a forest stage,” says Wilson.

FACTFILES

FORD ESCORT TWIN CAM

Sold/number built 1968-’71/1263 Construction steel monocoque Engine iron-block, alloy-head, chain-driven dohc 1558cc ‘four’ with twin Weber 40DCOE carburettors Max power 110bhp @ 6000rpm Max torque 107lb ft @ 4500rpm Transmission four-speed manual (optional five-speed), driving rear wheels Suspension: front independent, by MacPherson struts, anti-roll bar rear live axle, semi-elliptic leaf springs, telescopic dampers, radius arms Steering rack and pinion Brakes 91/2in (244mm) front discs, 9in (229mm) rear drums, with servo Length 13ft 1/2in (3978mm) Width 5ft 13/4in (1570mm) Height 4ft 5in (1346mm) Wheelbase 7ft 101/2in (2400mm) Weight 1730lb (785kg) 0-60mph 8.7 secs Top speed 111mph Mpg 23.4 Price new £1123 

FORD ESCORT RS1600 (where different to Twin Cam)

Sold/number built 1970-’74/947 Engine all-alloy (early cars iron-block), belt-driven dohc 1601cc ‘four’, with twin Weber carburettors Max power 120bhp @ 6500rpm Max torque 112lb ft @ 4000rpm Weight 1920lb (870kg) 0-60mph 8.3 secs Top speed 113mph Mpg 25.2 Price new £1447

 

This article originally appeared in the June 2009 issue of Classic & Sports Car magazine, which retains the copyright to all words and images. Click here to see our terms and conditions. 

Words: Graeme Hurst; pictures: Tony Baker