mk2 cortina

Not sure what the differences are between the 16v and 8v in terms of rwd installation (water outlets etc.) but the 8v is an easy engine to get into a capri/cortina engine bay, I even used the original sump. The biggest mechanical issue was that you need to thin the flywheel by 9mm to mate to the Type 9 but even that isn't a big job, I just handed over to a good machine shop.

There are a few cars out there with the 2.3 from a rwd Scorpio, and by all accounts it seemed as easy to fit in the space as the 8v. At worst I guess you might need to get an 8v to rob some bits to install the RS2000 16v (at a guess the sump and mebbe flywheel). Have also heard of people mixing and matching blocks and heads to get an easier install (or to upgrade an existing 8v)

The bigger job is probably how you run it. I'm running the stock ecu from the Sierra, and once you get your head around the wiring this is basically plug and play (there's even a chap on ebay selling the loom etc already stripped back to what you need). I believe the RS2000 uses a similar ecu setup to the 8v so should be pretty easy, but I think the 2.3 has a more advanced immobilized so you need additional stuff like the original key, lock barrel and dash? If you stick carbs and aftermarket ignition on it (or a full aftermarket ecu setup) then you'd avoid this though.

Probably worth an ask on Turbosport, sure there's a guy on there with the 2.3 running the standard ecu who'll know lots more than me about these later DOHC engines.

But if you're just using the car for road, and don't want to rip up the tarmac all that much and still get 40mpg the 8v is a surprisingly good motor, I love it in Laurens Capri - happy to take you out in it so you can see if the easier 8v setup would suit your needs trust me it isn't slow, and to be honest is perfect for a road car, very torquey and easy to drive and you only need basic suspension and brake improvements to make it feel capable of dealing with the new motor.