Don't know if its the same; but when I re-cat'ed my Esprit to 200 cells, I did a hard reset on my ECU causing it to retune (relearn).
But Elige have MAF, not MAP sensors... That could be the controlling item
I have no idea how a v8 Esprit works, unfortunately. I don't have a lot of experience with my Lotus Exige as of yet either...But I do have lots of experience with other cars.
When you remove the cat from most OBD-II compliant cars, a cel is often triggered because the oxygen sensor that sits post-cat in the exhaust is no longer happy. To be happy, the ecu wants to see a differential in the readings between the o2 sensor that sits pre-cat and the one that sits post-cat. That is how the ecu can tell that the cat is working. If it thinks the cat is not working, the ecu can/may/will do a few things.
1. It can throw a CEL. "Hey, I think something is broken. I should let the owner know."
2. It can start adjusting the a/f. "I'm seeing weird numbers. I should adjust the a/f till I see the readings I want."
3. It can stick itself into closed loop mode. "I don't have all the data I need to safely/properly adjust the a/f. As a result, I'm switching over to a map that I know will work until we get fixed."
All these things can lead to decreased performance and increase fuel usage.
So, what I'm getting at is, if you remove the cat and you do not have a way of tricking the ecu into thinking the cat is operating as it should (via adjustments to the ecu or an 02 sensor hack), you will often see no performance gain by removing your cats.