There's more than enough room on the chip to do sowftware switcing, and several routines posted here that do just that. If hardware switching is what you're after, that too is discussed. As long as the chip is the same package time (psop44), the speeds are good. I generally use SD's as that's what I can get cheap.

I have tried to do both google site search, internal search and advanced search, nothing brought any useful results,
could you please paste links to these posts?
Software switch is ok, i think codeword can trigger different address, but i will have to always keep laptop in my car to do the switch with vagcom,
while hardware all i need is to shut down the engine do switch and go ahead.

If i'm correct all i need to do is to install switch between pin 23  - VCC +5.0 V single power supply and mainborad.
or is there anything else i should know before?

But you could (in theory) replace a number of map lookups with hacked code to check some sort of ram location (or ECU input, or adaptation value) to decide on a map to use at run time..

Unfortunately i'm dumb in assembler and software solution for me would introduce more problems rather than solutions.
So i'm still opting for hardware switch. It would be placed on ecu and to switch you would have to open bonnet,
so unplugging battery is 10 seconds job.

Reading the sheet now i think that one of the pins should be switchable either CE# = Chip enable or OE# = Output enable,
If someone had success with that particular chip could you enlighten us please?