I put in a new motor into my car. i install a jdm gsr motor. i had a usdm gsr motor and it blew. right now the jdm gsr motor is not reaching the redline. it is hitting around 6000 to 7000 range. i hear that it is my ecu. what can i do?

 

are you using the old ecu or you also change the ecu
if you change the ecu try to put the old one back and see what happend