What Is The Difference Between The Gsr Ecu And A Si Ecu Other Then The Rpm Restriction???im Runnin Mine Off Of A Si Ecu.

you said you got a jdm gsr right? do you mean the ecu is a si-r or just a usdm si? the si-r i have been told is the same or close to the gsr in japan but im not completley sure

The GSR ECU controls the secondaries on the GSR intake manifold. The SI ECU will not control them.