I just did this myself. 615cc Nismo injectors with a new eprom for my JWT ECU. I bought the adapters and new syle connectors from Z1. The eprom was $100. The adapter design didn't require as much grinding on the plennum to make the #1 injector clear compared to the other designs out there and it was less money than going with the 300 Degree rails. Car runs better than the day I bought it 6 years ago with brand new 555cc Nismo injectors in it at the time.