We get asked this question all the time, so I decided to put a short page up about it. The basic question is this.
If I buy DSMLink now and upgrade to larger injectors later, do I need a new chip?
The answer depends on how large a change you're making and which version of DSMLink you're running.
The latest version of our product, ECMLink (V3), permanently records the changes you make to flash when you turn the ignition key off. So there is absolutely NO need for a new chip with new defaults. It simply doesn't have any meaning here. Any change you make is recorded permanently already. So there really are no defaults to change.
The 1G DSMLink package includes a memory board that permanently records any changes you make via the laptop to persistent RAM. You could remove the ECU from the car and set it on a shelf for 10 years, but the DSMLink settings you put into it before being removed would still be there. In this case, there's no need for a new chip with new battery reset defaults because the 1G really doesn't have the concept of a battery reset default.
The 2G DSMLink package uses the ECU's built-in, battery-backed RAM to store configuration changes you make via the laptop. That means as long as battery power is maintained to the ECU, your changes are saved. But if you disconnect the battery in the car, the DSMLink settings will revert back to the settings the chip was originally ordered for.
The user's manual (V2) or the integrated help file (V3) has a good section on how to dial in new injectors. Please read this section! We also have a short page on this wiki with some injector starting points suggested by our users and a more complete Fuel Setting page too.