Hello and welcome. Another American user.

Have you got any pictures of this split port CVH head?

We didn't have many different head types over here apart from mild changes to the port shapes and a lean burn head wich had a heart shaped combustion chamber. It would be good to see this split port head.

As standard the RS Turbo 1.6 CVH ran on Bosch KE-Jetronic and Ford's own ESC 2 ignition ECU. They used a hall effect sensor in the distributor to trigger the spark rather than a crank and cam position sensor. They then switched to EEC4 management on the Fiesta RS Turbo but I can't remember how, if at all, they monitored the cam position. The later blocks had a crank position sensor below number 4 exhaust port and monitored notches on the flywheel.

I have looked on your cardomain site and noticed a couple of things. The CVH RS Turbo standard turbo has a 0.36 turbine housing and a 0.42 compressor housing. I assume your turbo you have is nopt a standard unit?

Also the Cosworth YB engine has no similarities with the CVH at all. It is a Pinto block which is a 2 litre variant of what I believe is the Lima engine in the XR4Ti's. The head casting is one on it's own. The 16 valve Zetec is very similar the the CVH however.

There are countless topics on here related to the RS Turbo CVH. People on here have a lot of experience with them and convert them from Bosch KE-jet to Autronic and various other engine management systems. The RS engine is only a 1.6 litre engine but has been known to produce over 300bhp using steel internals. Some people use the 1.9 engine and others use the Zetec block and modify it to fit the 8 valve CVH head and make a 2.1 litre engine. Others just build a complete 2.1 litre full Zetec turbo.