This section establishes the main features of the different variants of Mk2 Lotus Cortina, and identifies the changes that were implemented from Aug ’66 to Aug ’70.

Note that the dates used are the dates from which the changes were made at the factory, as per the parts book. These dates tie in with the date code on the chassis plate of the car. That date of manufacture of the car, along with the chassis number, was allocated when Ford had completed their part of the manufacture of the car. The car could be registered on the road a couple of months after manufacturing date.

This is further complicated by the launch dates of new models (Series 1b, Series 2) which could be up to 3 months after the date of manufacture. For example, the earliest Series 2 cars started to be built at Dagenham in August 1967, but they weren’t launched until the Motor show in October 1967.

All this lot means that no dates given can be assumed to be absolute (even when printed in the Parts Manual) as there are always transition cars where a later car may be using up the components that should have been phased out on an older car. On this document, when the dates are in brackets, that means that this isn’t a recorded change, but the date is approximated from experience.

The section is structured in four sets of information:

Background

Introduction To Lotus Cortina Features

Mk2 Lotus Cortina Variants

Mk2 Features and Changes

A more detailed look at changes, together with detailed pictures, is in the next section ‘ Mk 2 Originality’

 

Background

The Mk2 Cortina went into production after the summer holidays at Dagenham in 1966, when the Mk1 Cortina lines were taken down, and the Mk2 Cortina lines built.

The Mk2 Cortina was launched in September 1966 with a full range of cars, with one notable absence…..the Lotus Cortina.

At the same time, Lotus Cars were moving from Cheshunt to a new purpose built factory in Hethel. This was to have an influence on the decision that the new Mk2 Lotus Cortina was to be fully built in-house at Dagenham.

Ford had seen the advantages and kudos of having a car representing their products in Motor Sport. The success of the Mk1 Lotus Cortina on the track from the very beginning was fantastic, and eventually, after putting the Lotus Cortina ‘back’ to near-Ford standard leaf spring rear suspension, the car became successful in rallying, but only in it’s last year of production.

Ford had learnt a lot from the MK1 Lotus Cortina experience. Over it’s short three and a half year life, they slowly changed the specification of the car to a more standard Cortina specification, which reduced production costs, reduced warrantee costs and improved reliability, all without a reduction in the perceived ‘sportiness’ of the car.

So when Ford came to develop the Mk2 Lotus Cortina, a principle design brief was to base the Lotus Cortina on the existing GT 2 door in order to keep costs down and simplify the manufacturing process.  The decision to build the car in-house was made, and on the same assembly line as the GT. This was primarily to maintain quality standards, but also taking into account the logistics of bodyshell transportation to Norfolk.

Gone was the different strut length, cast track control arms for the Lotus only, straight steering arms, and the reverse-eye rear springs of the Mk1 Lotus. On the Mk2 it was decided to use beefed up / lowered versions of the GT components. The interior was nearly all GT with the 1600E steering wheel on the Series 1b and Series 2 cars, but the Lotus Cortina did have it’s own speedometer and tachometer, calibrated to a higher speed and RPM.

The bodyshell shared the same strengthening parts as the ‘Heavy Duty’ export GT shells, that is the strengthening panels around the front strut tops and the  double skin rear chassis rails, between the spring hangers. Additionally, the front wings were rolled to provide additional clearance for wider wheels when used. Interestingly, the domestic 1600E had all the same strengthening features and rolled arches, as it used all the Lotus suspension and wide wheels. The 2 door 1600E shell is virtually identical to the Lotus shell, but of course with the battery mounted in the boot, the different washer bottle and throttle cable arrangements, there are minor differences.

The Mk1 Lotus Cortina ‘DNA’ shows through in the overall layout of the Mk2 Lotus Cortina. The same engine and gearbox were employed, but only the S/E version of the engine was installed in the MK2. The front mounted Girling servo with front running vacuum pipe, the split propshaft, the battery-in-the-boot are very familiar, as are the standard 5.5J steel wheels and Lotus roundels on the flanks of the car.

Something that was obviously new when the bonnet was lifted was the air filter setup, which was a large filter can sitting diagonally across the engine. This was selected by the lads at Boreham as a system that was more efficient at filtration, quieter, and quicker to change the element, than the system employed on the MK1 Lotus Cortina that was borrowed from the Elan.

 

Introduction To Lotus Cortina Features

What are the unique features of a Lotus Cortina? The detailed section below gives chapter and verse about this, and the Parts manual and Workshop manual complete the next level of detail!

But in general, and to get the ‘big picture’ of what a Lotus Cortina looks like, here’s a very high level pointer.

The body code for the lotus Cortina is 91, with the first 4 characters of the chassis code being ‘BA91’

The Mk2 Lotus Cortina is based upon the 2 door GT, with some minor changes in the shell to accommodate the battery in the boot, the layout required by the Twincam engine, the anti-tramp bars on the back axle and the split propshaft.

The bodyshell is a 2 door heavy duty shell. That means it had an extra panel spot-welded around the strut tops in the engine bay, strengthening panels around the strut tower inside the wheel arch and double skin strengthening in the chassis rails between the rear spring mounting points.

It also has the battery tray mounted in the boot, and of course, no battery tray under the bonnet. The car has anti-tramp bars fitted to the back axle, which require brackets on the shell to attach.

As the car has a spilt propshaft, it has a central bearing carrier which fixed to the floor pan.

Under the bonnet, there is obviously a Twincam engine. It has a unique air filter system, using a large air cleaner going across the cam covers.

There is a Girling servo fitted to the front of the left inner wing, with a metal vacuum pipe connecting it to the inlet manifold which runs along the rear of the slam panel.

The solenoid it fitted to the right side of the plenum chamber on two plastic feet, and the carburettors use an accelerator cable (rather than rods), which is fastened to the right side inner wing as it goes into the bulkhead.

A washer bottle is used on the Lotus fitted behind the servo on the left hand inner wing.

The Lotus Cortina Series 2 has a unique wiring loom, with the voltage regulator on the right side inner wing.

Inside the car, both the speedometer and tachometer have black bezels. The speedometer reads to 140mph, and the tachometer has a redline from 6500 to 8000 rpm. The trim is the same as the GT, and the steering wheel is the same as the 1600E. The accelerator pedal is unique to the Lotus as it enables the use of the throttle cable.

Inside the boot, the battery is mounted on the right side. On the left side is the spare wheel, and just inside the spare wheel well is a hook, that allows a bungee to be hooked over to hold the tool roll in place. The bungee is attached at two points on the boot floor via rubber rawl plugs,

The spare wheel clamp is larger than the standard Cortina clamps, but the same as the 1600E clamp, in order to secure the wider, 5.5J wheel.

That’s the basic introduction to the Lotus Cortina features. Have a look in the ‘Mk2 road Car Studies’ section to see these bits and pieces in context. Then read the detail below!

 

Mk2 Lotus Cortina Variants

There are 3 variants of Mk2 Lotus Cortina,

Series 1a, launched in March 1967

Series 1b, launched in September 1967

Series 2, launched in September 1968.

Like the Mk1 Lotus Cortina, those variations are mainly defined by changes in the base Ford Cortina models. The specific Lotus Cortina bits, that is, the engine, servo, air cleaner, split propshaft, battery in the boot and lowered suspension, changed very little across the three variants.

Note that the Mk2 Lotus Cortina was available in the full range of GT colours, although the vast majority (maybe up to 80%) were Ermine White, with a guesstimate of 10% Red (Dragoon or Red II 65), 5% Blue Mink / Silver Fox and 5% the rest. The cars were available in both right hand and left hand drive from the beginning. The full range of trim colours was also available, but the vast majority of cars had black trim.

Like the Mk1, the Mk2 Lotus Cortina didn’t have a stripe painted on at Dagenham. It was offered as a dealer ‘fit’ option, and the dealers were supplied with a template and painting location instructions. A copy of these are in this section.

The Mk2 Lotus Cortina helped to inspire another Cortina model that was launched in October 1967, the Cortina 1600E. That also used the heavy duty shell employed by the Lotus, but (mainly) in 4 door form. It used the gearbox, back axle, rear brakes, front brakes, rear suspension, front suspension and steering of the Lotus Cortina, and had the same dashboard layout as both the GT and Lotus. One company, Luton Motors, offered a twincam conversion for the 1600E, called the Lumo.

 

Mk2 Features and Changes

This section examines the changes to the Mk2 Lotus Cortina over it’s three variants.

At this stage, detailed mechanical changes such as changes to bearings, materials employed etc., are not covered. The Parts Manual for the Cortina Mk2 identifies these well enough. Major changes to mechanical sub-assemblies are identified, such as the change from the 3 rail gearbox to the single rail, and the change in split propshaft between the Series 1 and Series 2 cars, but only at that high level.

The changes identified are more to be able to identify what variant you are looking at, by examining the features of the bodywork, interior, under bonnet and inside the boot.

As was the case for the Mk1 Lotus Cortina, most of the changes to the Mk2 Lotus Cortina came about because of the changes to the underlying Ford models….the bodyshell, interior trim, gearbox, dash layout, chrome trim, etc. The changes for the Lotus variations from the GT were quite small. Therefore, the variants of the Mk2 Lotus Cortina are examined below from 2 different perspectives:

The changes due to the changes in the underlying (Cortina GT) model

The changes due to the Lotus-only (Lotus Cortina Variation) specification change.

The Series 1a is defined below with ‘features’ rather than ‘changes’ to establish the baseline from which changes were made.

This section will be populated with photos of the changes over time.

SERIES 1a

Series 1a Bodyshell – General Ford Features

Heavy duty 2 door GT shell as basis, with front strut strengthening panels, double skinned rear chassis members.

Anti-tramp bar brackets (as per Series 1 GT)

Windscreen pillar curved at doors with curved roof drip rails and trim

574 mm tall windscreen and appropriate rubbers fitted

External bonnet release with red ‘Cortina’ badge

Flange and weather strip at rear of engine bay

 

Series 1a Bodyshell –  Lotus Cortina Variation Features

Revised bulkhead holes for throttle cable / lack of throttle shaft.

Mounting points for split propshaft centre bearing carrier.

Boot mounted battery carrier with a top mounted bracket to secure battery.

Hook in spare wheel well for bungee tool locating strap, attached to boot floor by two large screws.

No hooks on inner wing for washer bag.

Lotus ’roundel’ fitted on each rear wing towards the rear (as per Mk1)

Lotus ’roundel’ on left side of  rear panel.

5.5 inch J steel rims with hubcaps

Oval ‘Ford‘ badges fitted to the lower rear of BOTH front wings. Usually only one on the passenger side.

 

Series 1a Interior – General Ford Features

Mk1 Heater and controls, with push / pull knobs above ashtray, and pipes exiting through the bulkhead on the right side (driver side on RHD).

Dash ‘Aeroflow’ Vent Type ‘A’ fitted (as per Mk1) with 2 windscreen de-mist vents

Minor instruments on dash in ‘pod’

Under-dash umbrella style handbrake

Standard ‘Bakelite’ GT Steering Wheel

Standard round GT gear knob

Indicator / flash / horn arm revised angle for shorter steering wheel boss

Short centre console with armrest / cubby no clock (GT). Aluminium plate under rear ashtray has horizontal grooves

Ribbed non-folding, tilt forward front seats with plastic kick guards as per Mk1. Trim pattern similar with extended ‘rib’ at top of back rest. Seats are non-locking. Seat adjusters have rubber finger grips.

Full width padded parcel shelf on passenger side as per Mk1

Lodestar headlining

Smaller Winguard 6 inch internal mirror with rounded return stem as per Mk1

Internal door and window winder handles as per Mk1

28tpi thread on steering column

Door sealing rubbers have pointed ‘edge’.

Series 1a Interior – Lotus Cortina Variation Features

Speedometer reading to 140mph, Tachometer reading to 8000 rpm, black bezel.

Exposed painted parts (door tops etc,) in low gloss / satin black in most cases where black trim fitted, but could be body colour where other trim fitted / external colour non-white.

Series 1a Under Bonnet – General Ford Features

A weather strip / flange runs along the back of the bulkhead.

The electrical system is not fused.

The bonnet is opened from the outside via a button above the red ‘Cortina’ badge in the centre of the grille

Early cars had a braced bonnet

Roller-Type front struts with large plastic caps.

25amp voltage reguator fitted (GT only and some export markets)

Series 1a Under Bonnet – Lotus Cortina Variation Features

Lotus Twincam S/E specification engine fitted, with Weber 40DCOE 18 carburettors.

Raised ‘Lotus’ script cast into both sides of unpainted cam cover. Same cover for Mk1 Lotus Cortina and Elan. Round Oil cap fitted to cam cover. Standard Ford metal twin blade fan.

Large AC air filter canister fitted diagonally on top of engine, with connection rubber tube to Bakelite / plastic carburetor cover.

3 rail 2000E ratio gearbox (reverse gear to the right and down) and a split sliding spline propshaft (as per Mk1 Lotus Cortina)

Push button starter solenoid fitted on plenum chamber, mounted on plastic block.

Throttle cable fitted with heavy duty bracket securing cable before entering bulkhead. Special throttle pedal fitted to take cable.

Girling Type 2a servo fitted at front / left of engine bay with metal pipe and rubber hose connection to inlet manifold (similar to Mk1)

Large header radiator (as per Mk1)

Large plastic cylindrical washer bottle is fitted in a cage, replacing the ‘bladder’ style with hooks. Unique to Lotus and export right hand drive cars fitted with duel circuit brakes (that require their battery tray to be moved to the left side inner wing)

Non-fused electrical system

25 amp Voltage Regulator fitted as per GT.

 

Series 1a Boot – General Ford Features

Ribbed, flat top petrol tank fitted.

Series 1a Boot – Lotus Cortina Variation Features

Battery is mounted inside the boot on an ‘early’ type battery tray with top mounting battery clamp.

Spare wheel is mounted in the wheel well, and a hook in the well enables a bungee cord attached to the boot floor, via two screws, to be attached to secure the jack and wheelbrace bag. Both bungee and hook are attached via screws set in expanding rubber collars, fitted to pre-drilled holes.

 

SERIES 1b

The Series 1b, launched in September 1967,  came about principally because Ford introduced the new crossflow engine in the standard Cortinas, and that required the heater pipes to exit from the left side rather than the right. This was a good opportunity to upgrade the heater controls and the other minor controls on the dashboard.

The new 1600E was launched at the same time, and it’s sporty steering wheel replaced the plain black GT wheel in the Lotus Cortina.

Series 1b Bodyshell – General Ford Changes

Heater pipe bulkhead exit changed from right side to left side

Series 1b Bodyshell –  Lotus Cortina Variation Changes

Lotus ‘Roundel’ removed from rear panel

‘Twin Cam’ badge added to boot lid below ‘Cortina’ badge

Extra ‘Ford’ badge on driver side front wing deleted.

Series 1b Interior – General Ford Changes

Heater and controls updated to slider controls above ashtray, and pipes exiting through the bulkhead on the left side.

Revised Dash ‘Aeroflow’ Vent (Type ‘B’) fitted. These had internal flaps to open / close air supply.

Standard pear shaped gear knob replaces standard round GT gear knob

Long centre console with clock replaces short centre console

Front seats lock into position.

Series 1b Interior – Lotus Cortina Variation Features

As above, plus:

Standard (short boss) 1600E steering wheel replaces Standard ‘Bakelite’ GT Steering Wheel

 

Series 1b Under Bonnet – General Ford Changes

Strut tops changed to non-roller type

Series 1b Under Bonnet – Lotus Cortina Variation Changes

Cam cover changed to have ‘Lotus’ cast on front, replacing side cast letters. Cam cover unpainted, and used on all Lotus Twincam engines of this period.

Three eared oil cap fitted.

Weber 40 DCOE Type 31 carburettors employed shortly after the introduction of the Series 1b.

Lighter weight throttle cable bracket replaces earlier heavy duty bracket

Non-button operated solenoid, still mounted on plenum on plastic mounts

 

Series 1b Boot – General Ford Changes

No changes

Series 1b Boot – Lotus Cortina Variation Changes

No changes

 

SERIES 2

The Series 2, announced in September 1968, was a major, mid-term Ford facelift for the Mk2. The Lotus changes were very small.

Series 2 Bodyshell – General Ford Changes

F.O.R.D badges fixed to bonnet and boot.

Chrome strips and corner pieces fitted horizontally on rear panel, above and below rear light clusters.

Windscreen pillar revised shape at doors with straight roof drip rails and trim.

Revised windscreen height to 580mm, with appropriate rubbers fitted.

Internal bonnet release with blue ‘Cortina’ badge replacing red badge.

Flange and weather strip at rear of engine bay deleted.

Revised dash / steering column mounting panel (GT, 1600E and Lotus)

Modified transmission tunnel to accommodate single rail gearbox, which is 1 inch longer that the 3 rail box.

Small indentations on top / rear  of the front inner wings to facilitate access to master cylinders (both sides of bay to accommodate RHD and LHD).

 

Series 2 Bodyshell –  Lotus Cortina Variation Changes

Revised mounting points for split propshaft centre bearing carrier.

 

Series 2 Interior – General Ford Changes

Revised dash layout with minor instruments set into main dash.

Revised Aeroflow fresh air controls, with 4 windscreen de-mist vents on top.

Revised control knobs.

Hand brake mounted on centre tunnel with revised centre console (no arm rest).

Short parcel shelf fitted on passenger side.

Re-styled seats with new covers and tilting back. Optional reclining facility.

Moonstone (or putty) headlining replaces Lodestar pattern

Revised door handles and window winder handles

Long-boss end-tapered 1600E steering wheel fitted

18tpi thread on steering column

Oval Ford badge on sill tread plates (both sides) and revised screw location for plates

Revised rounded door sealing rubbers

Series 2 Interior – Lotus Cortina Variation Changes

No changes beyond standard Ford changes for GT and 1600E.

Speedometer and tachometer positions changed for Lotus.

Series 2 Under Bonnet – General Ford Changes

Bonnet release cable runs along right hand inner wing

Fused wiring system employed with fusebox mounted on right hand inner wing

Revised brake pipe layout.

Engine bay wiring loom revised to single loom from 2 jointed looms.

Umbrella handbrake cable / pulley system at bulkhead deleted.

Series 2 Under Bonnet – Lotus Cortina Variation Changes

New wiring loom with regulator mounted on right-hand inner wing

Girling Type 2b servo, with band around vacuum tank, replaces Type 2a.

Single rail  2000E ratio gearbox (reverse gear to the left and up) fitted replacing the 3 rail gearbox. New gearbox as per 1600E, still with the 2000E ratios.

Split non-sliding spline propshaft replaces the sliding spline propshaft with revised centre bearing. 1 inch shorter than the previous propshaft due to increased length of single rail gearbox.

 

Series 2 Boot – General Ford Features

Petrol Tank top revised to have raised corners (to reduce drumming)

Petrol tank sender revised to delete lock ring (Aug 1969 to end of production)

Series 2 Boot –  Lotus Cortina Variation Features

 

No changes.