Ford Cortina Mk3, Mk4 & Mk5 Tuning Guide
Ford had been successful with the "four-year cycle" of the previous two Cortinas in a bid to keep the model fresh. When the Mk3 was launched in 1970 they decided to try and move the Cortina up-market and enhance profitability. The Mk3 was treated to several years and kept in production for six years helping the Cortina to remain the best selling car in Britain for four years running. The mid 70s saw the "Coke Bottle" fashion passing and so the Mk4 Cortina retained essentially the same running gear but was given a much boxier body and this continued on to the Mk5 Cortina which was essentially just a facelifted Mk4 with the platform of the MK3. Engines were Crossflow and Pinto in the Mk3 and then the Cologne V6 was added to the Mk4 and 5.
The later Cortinas are far too heavy for a Crossflow so the easy and basic conversion for any Mk3,4 or 5 is a 2.0 Pinto although the rep-mobile nature of the car would probably welcome some lazy power in the form of the 3.0 Essex or the 2.8 Cologne. Both of which will fit with minimal fuss. If you want to drag your Cortina into modern times then we suggest a BOA or BOB 24 valve V6 Cosworth. If it’s mad performance that you are after then of course the Pinto based Cosworth YB Turbo will go in on standard Pinto engine mounts. Those of you looking for something different might consider the Zetec or even the Duratec engine. The engines were obviously originally intended to power the front wheels of a Mondeo but you will find the required conversion parts to turn them around the other way in this catalogue. Given that the Mk3 onwards now had a steering rack, you’ll run into less problems when it comes to mounting engines with rear-drop sumps.
You shouldn’t run into many problems when up-grading the gearbox of your late Cortina, a Type-9 five-speed should slot nicely in-place of the original four-speed and the tunnel is plenty large enough for a T5 or MT75. The Type-9 will give the Cortina a bit longer legs on motorway runs and we can supply a completely re-built unit with no need for you to find an exchange one. We also stock a wide range of bellhousings to really give you a huge choice of what engine and gearbox combination to choose. Most 2.0 and 2.3 Cortinas came with an Atlas axle but the smaller engined models had a smaller and weaker version of it. Note that most Mk5 Crusader models were also fitted with this smaller axle regardless of engine. If you’re planning any sort of power up-grade then a stronger axle from a bigger engined model is recommended. With power up-grades it is a sensible modification to fit a limited slip differential to help get the power to the floor, and if you need further advice our sales team would be happy to advise on what would best suit your application.
The later Cortinas enjoyed a new kind of suspension layout with a steering rack and wishbone suspension at the front along with coil springs at the rear. The first job for any late Cortina is certainly to uprate the bushes in the suspension and the subframes. After this a set of lowering springs will then improve handling and the looks of the car. If you want to get more serious about the handling you could then look at fitting uprated dampers all around. As luck would have it, Cortina based suspension would find its way onto many kit cars, which means that there is a wide range of brake conversions available. From a simple set of uprated discs and pads, right through to big brake conversions, the late Cortina is as well catered for as the reardrive Escort in this area. Pedal feel can be improved by simply adding some braided flexible lines.
The late Cortina is not by any means a performance vehicle but with the right modifications it can be made into a retro looking, modern day, cruiser with refinement and performance all in one.