Sorry Phil, i didnt really give a lot of detail there mate.

Basically this is for my girlfriends car, which is a calibra turbo.

The ecu in it is actually far from more basic than an L8, its actually really quite clever, its "adaptive"

It looks at the corrections it is making during closed loop fuelling and uses them to alter its own internal injector scaling tables, so that if you fit bigger injectors, it "learns" them.

But there is a limit to how far it can adjust like this, and if you put an injector in that is too big, it wont be able to get the fuelling lean enough.

Obvioulsy a live map or new chip would sort this, but there are VERY few people who have the equipment to do that on this ECU (motronic 2.7, might even be the same as in your 348 as i know they are used in some ferraris of that era) so i was hoping to get away with an "off the shelf" chip if possible just becaues of the hassle/expense of her having to take it up to Stu.