ENGINE UPGRADES
Despite being an old design, the Pre-Crossflow engine has had its fair share of followers over the years. Back when they were first released, Broadspeed and Cosworth amongst others had a hand in extracting more power and turning them into screamers on the track. However, in more recent years owners have chosen to swap engines in order to chase performance but if you’ve decided to keep it as Ford intended and use what you’ve got then the Pre-Crossflow can be turned into a real period-looking punch packer.
The original powerplant for the Cortina came with two capacity options: 1200cc and 1500cc. It is of course advisable to use the latter as a starting platform as they were more powerful and came with a five-bearing crank which is handy. Upgrading to GT spec is straightforward with the help of modern parts. This will mean the addition of a Weber 28/36 DCD or a similar twin choke from a later Crossflow and a matching uprated manifold and exhaust system (try 105speed). Together with an uprated cam that has similar specs to the original GT version, such as the Kent BCF1 you will be knocking on the door to GT power.
From there, a Stage 1 head from the likes of Burton Power or Throbnozzle Racing along with a better cam such as the Kent BCF2 and a tubular manifold and exhaust will give around 95 bhp, which makes for a nice road engine.The single carb will be able to fuel the engine further but everyone likes the sight and sound of a set of twin 40s under the bonnet so ideally those would be next on the list and this will unleash another 10-15 bhp or so. By now a Stage 2 head along with an even hotter cam such as the Kent 234 will give a steady 120 bhp. Of course, going beyond that and it starts getting a bit more specialist and expensive but we’ve seen examples with over 150 bhp before so the potential’s there. If you are intending a big-spec build from the start then capacity can be increased to almost 1650cc and compression can be raised quite significantly by skimming the head. But make sure you know what head you have to start out with as there are different variations that will of course give different compression ratios.
“EVERYONE LIKES THE SIGHT AND SOUND OF A PAIR OF TWIN 40s UNDER THE BONNET”