slapping some carbs on a 20v.

[Diamond Hell]

will the carbs show a better performance than just a specially made map.

Extremely unlikely.

The problem you have is that without the schematics for the wiring you're looking at a big pile of spaghetti AND you have no idea what the ECU is doing.

For performance the best thing to do with your car (as I think I've suggested before) is to get it set up with Emerald Management and get Dave Walker to map it.

For ease of getting it running the best thing to do is to go bike carbs, but as I said in this topic, you still have the problem of getting your ignition sorted.

The biggest problem you have with the car's current set up is lack of documentation, isn't it?  You really need some time with whoever did the conversion, to get their logic explained.

[richard s]

if going the route of engine management would it not be better to run bike throttle bodies opposed to carbs

[Diamond Hell]

If you're managing the injection you would absolutely need to go 'throttle bodies' rather than carbs..... although a carb is a throttle body, of sorts. 

The difference is that carbs (with their rotating throttle plates) are mechanically controlling fuel injection and vaporisation when they are operated, whereas throttle bodies (with their rotating throttle plates) have electronically controlled injectors that are managed according to the needs of ECU feedback-controlled parameters..... there is no way of running carbs on electronic management - they 'just squirt fuel'. 

If you're running carbs you can still manage the sparks electronically through simple standalone ignition management.

Throttle bodies plus electronic injectors are used where the injection is controlled electronically, as well as the sparks - this is far more complex and expensive (but a better solution). 

As a quick fix I suggested to this guy to go carbs with (relatively simple) electronic ignition of some sort.  His 20V doesn't use a dizzi, hence he doesn't have the option (unless there's a blanking plate on the block or head where a dizzi could go) to run mechanical (dizzi-based) ignition.