

The Lotus-Cortina, the car sometimes known as 'the original fast Ford', appeared in January 1963. There was an increasing demand for sporty cars, and in the USA the relationship between racing success and sales success was being realised. In the early '60s Ford implemented a worldwide policy of 'Total Performance', and each Ford division was left to its own devices. The Lotus-Cortina was the brainchild of the Ford of Britain Public Affairs chief at the time, Walter Hayes. He went on to take part in the founding of the Ford Advanced Vehicle Operation (FAVO), which was later responsible for such efforts as the GT40 and the Escort RS models. The Lotus-Cortina was conceived and developed rapidly, as anyone who owned one and had the rear suspension collapse will tell you. So how did Lotus fit into the scheme of things? At the time Lotus were developing a twin-cam engine based on the bottom end of Ford's 1499cc power plant for their Elan, and Hayes knew Lotus boss Colin Chapman personally. Hayes put forward the proposal to Chapman of assembling 1000 Cortinas with the Lotus-Ford engine, so the car could be raced and rallied as a Group 2 production car. Group 1 cars had to be virtually the same as the average family car, but Group 2's could have modified engines, steering and suspension. The thumbs-up was given, and the Type 28 Lotus was born, eventually to be called 'Cortina developed by Lotus' by Ford and the 'Lotus-Cortina' by the rest of us. You could get yourself one for £1100.
The car succeeded magnificently in lifting Ford's performance image, with its rapid performance and taut and grippy handling making it a great success on both race tracks and rally courses. But it didn't do so much for building a reputation as a producer of reliable cars...
The Mk.I Lotus-Cortina was replaced by the all-round less tempestuous Mk.II in March '67, after 2894 were produced. Of these, it is estimated that about 1300 had the first suspension type. Lotus-Cortinas, especially the Mk.Is, are highly sought after now, and are still regularly used in historic racing events, such as Group N touring car racing in Australia (where they weren't sold), where you can see Lotus-Cortinas mixing it with cars such as Mini Cooper S's, EH Holdens, Ford Mustangs, and Alfas Giulias. It should be noted that the Lotus-Cortina was available in the USA. It became available on September 1, 1965, at the rather imposing price of $3420, clearly an attempt to sting those who wanted nothing more than to emulate Jim Clark at the Indy 500. However, when the Mk.II model arrived the Lotus-Cortina version was no longer officially available.
BODY
Unlike the Mk.II Lotus-Cortinas, the MkI. Lotus-Cortinas were developed and assembled by Lotus at their Cheshunt factory in North London. Lotus started with two-door sedan shells, to which was added lightweight alloy doors, bonnet, and boot lid, to aid racing success. To the boot area over the wheel arches tubular stiffening braces were added, to suit Lotus' rear suspension, and the boot also became the new home for the battery. The spare was also fitted to the boot floor, rather than in the wheel well. The alloy panels became optional equipment from October '64, when Ford gave the Cortina range an updating, and so the Lotus-Cortina picked up the same changes, including the wider grille, and a revised dash with flow-through 'Aeroflow' ventilation and the accompanying air outlets in the C-pillar. The bracing in the boot was discontinued in June 1965 with change to the more conventional Ford rear suspension.
And of course it would be remiss of me to say that all these cars were turned out in Ermine White with Lotus-green (Sherwood Green) striping and rear panel. The other feature of the paint job that set it apart from the standard Cortinas was the lack of rust protection measures, meaning fun and games for restorers down the track. Lotus-Cortinas also sport small 'bumperettes' up the front, and Lotus badges on the rear quarter panels and on the blacked-out front grille.
ENGINE
The Lotus-Cortina story the real interest is the donk. As mentioned, it was based on the five-bearing bottom end Cortina engine, and used many Ford parts, but it sure doesn't look much like the standard Cortina engines. The conversion was designed for Lotus by Harry Mundy. Initial designs were based on Ford's 1340cc three-bearing block as used in the Anglia Classic 109E, but the 1499cc (116E) was decided on for the Elan, which was bored out 82.55mm to give 1558cc, to suit the 1600cc competition class limit. Retained from the 116E was the crankshaft, connecting rods, and pistons. To this was added a Lotus-designed camshaft drive and aluminium cylinder head assembly.
"The engine's exceptional breathing and the reduction in reciprocating mass inherent in the overhead camshafts mean this diminutive Street Hemi cranks up frightful revs as a matter of course."
The twin-cam cylinder head used valves operated directly from the cam lobes by inverted bucket tappets enclosing coil springs, with two valves per cylinder. The head was a crossflow design, with the inlet manifolds being part of the same casting. Technically this was actually a three-camshaft engine, as the original Ford camshaft was retained to drive the oil pump and distributor, which resulted in a near impossible to reach distributor. Camshaft drive was by a long single-stage roller chain.
The juice was slurped in through two touchy horizontal double-barrel Weber 40DCOE carbies, and the engine was also fitted with a 6500rpm rev limiter, so the standard Ford bits wouldn't pack it in. The official Lotus performance figures were 105bhp at 5500rpm, with maimum torque of 108lb ft at 4000rpm. It's generally held that these figures are a bit hopeful (90bhp is quoted for the same engine in the Lotus Elan), but nevertheless, the Lotus-Cortina was and is renowned for its poke. The figures don't sound too shabby even now - top speed of 105mph, 0-60mph in just under 10 seconds, nearly 50mph in 1st, 70mph in 2nd, and 90mph in 3rd.
GEARBOX
Again Lotus started with standard Ford equipment, using bits and pieces from Cortinas and Corsairs, and the Lotus-Cortinas sported a four-speed floor shifter, with synchro on all four gears, and a hypoid bevel design rear axle. Like many bits of the Lotus-Cortinas, the gearboxes got less technical but more durable as they went on, and the gearboxes in particular seemed to be in a permanent state of change. The Lotus-Cortina was born with the gearbox developed for the Lotus Elan, with rallying in mind.
This gearbox featured very close gear ratios (to suit the lighter Elan), a diaphragm spring clutch, alloy case and clutch housing, and a remote control gearchange. Over the lifetime of the Mk.I Lotus-Cortina all these features disappeared or became optional. In July '64 the alloy parts were made optional extras, and the Elan gearbox ratios were made optional in favour of a modified GT gearbox featuring a higher 2nd gear ratio, the Elan ratios not proving to be too flash for road use. In October '65 the gearbox ratios were changed again in favour of the Corsiar 2000E gearbox, which came to be used in the GT and in the Escort Twin-Cam. The ratios of these gearboxes were as follows:
|
|
1st |
2nd |
3rd |
4th |
Reverse |
|
Elan close ratio: |
2.51 |
1.64 |
1.23 |
1.000 |
2.807:1 |
|
GT w/ uprated 2nd: |
3.543 |
2.04 |
1.412 |
1.000 |
3.963:1 |
|
Corsair 200E: |
2.972 |
2.01 |
1.397 |
1.000 |
3.324:1 |
SUSPENSION, BRAKES AND STEERING
The first Lotus-Cortinas had a single-piece propeller shaft, and a back axle with coil springs and located by radius arms and an A-bracket linked to a light alloy differential housing, and used a 3.90:1 final drive ratio. This setup placed excessive load on the differential housing, and the retaining bolts tended to come loose, which caused oil to drain out of the axle, destroying the diff, and with the leaking oil doing similar to the suspension bushes, causing surprise collapses. It also transmitted mysterious thumps and clunks into the cabin. In July '64 the light alloy diff housing became optional, and a two-piece propeller shaft was introduced. In June '65 the entire rear suspension was replaced by the setup used in the Cortina and Corsair GTs, half-elliptic leaf springs and twin radius arms. This setup proved to be far more durable, and nobody really noticed the difference anyway.
"By 1965, when that legendary European Championship season began, the Lotus Cortina was already a well-proven racing car. Even though it was somewhat fragile, especially in and around the rear suspension A-frame area, meticulous preparation and regular rebuilds usually kept the works-backed cars going."
Up the front was a simple McPherson strut suspension, and an anti-roll bar. The whole car was much lower than any other Cortina. Like the GT, the Lotus-Cortina had 5.5" wheel rims and Girling 9.5" front disc brakes and 9" rear drums. A vacuum booster was fitted. Recirculating ball steering was used, as on all other Cortinas.
INTERIOR AND TRIM
The first Lotus-Cortinas were pretty sparse inside, as they were designed with racing in mind. The dash used was to appear later in the '64 GT, and featured only basic instrumentation, with the exception of the tachometer. A centre console hid the remote-control gear change, and a Lotus wood-rimmed steering wheel was used. All trim and carpet was in black only.
Surprisingly enough, the standard of fit and finish is very high indeed and this has not been a particularly notable feature of Lotus products in the past. However, it appears that the object of the car is to offer a degree of luxury not usually found in small sedans, in addition to the car's superlative performance. The update that was introduced to the Cortina range in October '64 brought with it a new dash, with a full set of instruments, and that 'Aeroflow' ventilation. The dash was particularly good looking, with the instruments set in a simple brushed aluminium panel. The seat and door trims were updated.
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